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Shop By Brand

The Following brands are available based on your search.

  • ACDelco
    ACDelco
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    Bosch
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    Spectra
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    Standard Ignition
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    Walker

Best Selling Genuine Buick O2 Sensors

  • We Stock the following top leading brands, including Delphi, Denso, ACDelco
  • Constantly Updated Inventory of Buick Replacement O2 Sensor Parts
Delphi
1987 Buick Skyhawk Oxygen Sensor - Upstream 4 Cyl 2.0L Delphi

P311-4153959    ES10966  New

8251059010 , 8251627530 , 8953000886 , 94408151 , 25166816 , 25165118 , 3300 4243 , 18213-64B00 , SG17 , 8089903510 , 12013 , 8944081510 , 25162753 , 5S3072 , 25106073 , 1821364B00 , 53000886 , 11001 , 8990625 , 10042186 , 5S3936 , 213631 , 5014 780AA , 138101 , 2341001 , 2131165 , 25021001 , 8089907410 , 6003981 , FE972 , SG1249 , 1821360B00 , SU100 , 8-08990-351-0 , 234-1001 , 25132068 , 33004243 , 21002 , 8990789 , 5613725 , 8-97018-586-0 , 8192114370 , 250-21001 , 12014 , 8933004243 , AFS20 , DY-573 , 1821382010 , 8-08990-741-0 , SG5 , 25171581 , 21552 , 8251626000 , 8-25105-107-0 , SU4700 , 8-25162-693-0 , 8251626930 , 91171942 , DY-578 , 2135 , REA1001 , 0456288 , 97018586 , 213511 , 8990741 , 8251331850 , 25171572 , 25105901 , 8-25105-901-0 , 25176707 , 25171574 , 213502 , 25162693 , 5S3071 , 5300 0886 , AFS22 , 06003981 , 213503 , AFS21 , FE823 , 25162600 , DY578 , 8-25133-185-0 , OS701 , DY579 , 25165120 , 25171573 , 2131167 , 8-25162-753-0 , 8251668160 , 8-94408-151-0 , 0258002014 , DY573 , REA9119 , 213504 , 8-25166-816-0 , 18213-60B00 , AFS33 , 5613959 , 96060174 , AFS81 , 25133185 , 8970185860 , 1377953 , SG122 , OS102 , DY-579 , 25107378 , 21315 , 8990469 , 213500 , 19211437 , 25105107 , 8-25162-600-0 , SU1434 , 8251051070 , 18213-82010 , OS624 , SG12 , 5014780AA , 138-101 , 8-19211-437-0 , 19178953 , 25166169 , FE803

Qty:
$17.62
Delphi Oxygen Sensor  Upstream
  • Oxygen Sensor
  • 12.6in Length
  • Product Attributes:
    • Overall Length: 320.0
    • Sensor Type: Non Heated
    • Wire Quantity: 1
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 2
    • Most jobs typically require 2 of this item.
Brand: Delphi
Position: Upstream
Additional Fitment Information:
Vehicle Submodel Aspiration Fuel Type Position Block Engine CID CC
1987 - Buick Skyhawk Limited Naturally Aspirated GAS Upstream L 4 Cyl 2.0L 122 -
Delphi
1998 Buick Century Oxygen Sensor - Rear 6 Cyl 3.1L Delphi

P311-04CA5A9    ES20002  New

SU1295 , 8125872140 , 25312196 , SG277 , 19178922 , 8191789240 , 8-25164-983-0 , 5S3126 , OS229 , DY734 , 138266 , 2344025 , 8253122070 , SU1189 , 5S8134 , AFS141 , 25164983 , REA1010 , 5S8151 , DY-734 , 25312207 , AFS123 , SU1299 , 138752 , 21544 , 138-752 , 12578459 , 25318321 , 8-19178-924-0 , OS1072 , DY731 , 12587214 , AFS116 , 25161130 , FE6085 , 2344087 , 138-266 , 234-4025 , 11170 , 25024340 , DY-776 , 25132207 , 234-4087 , DY776 , 25132196 , 21528 , 138217 , 8251649830 , 8-25312-207-0 , DY-731 , 5S3125 , 19178924 , 5S3119 , 5S3116 , 13444 , 25327815 , AFS97 , 138-217 , SU1087 , 19178747 , 2131681 , OS825 , 8-12587-214-0

Qty:
$54.76
Delphi Oxygen Sensor  Rear
  • Oxygen Sensor
  • 18in Length
  • Product Attributes:
    • Connector Shape: Square
    • Overall Length: 320.0
    • Sensor Type: Heated
    • Wire Quantity: 4
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 4
    • Most jobs typically require 4 of this item.
Brand: Delphi
Position: Rear
Additional Fitment Information:
Vehicle Submodel Aspiration Fuel Type Position Block Engine CID CC
1998 - Buick Century Limited Naturally Aspirated GAS Rear V 6 Cyl 3.1L 189 -
Delphi
1987 Buick Regal Oxygen Sensor - Upstream 6 Cyl 3.8L Delphi

P311-4153959    ES10966  New

8251059010 , 8251627530 , 8953000886 , 94408151 , 25166816 , 25165118 , 3300 4243 , 18213-64B00 , SG17 , 8089903510 , 12013 , 8944081510 , 25162753 , 5S3072 , 25106073 , 1821364B00 , 53000886 , 11001 , 8990625 , 10042186 , 5S3936 , 213631 , 5014 780AA , 138101 , 2341001 , 2131165 , 25021001 , 8089907410 , 6003981 , FE972 , SG1249 , 1821360B00 , SU100 , 8-08990-351-0 , 234-1001 , 25132068 , 33004243 , 21002 , 8990789 , 5613725 , 8-97018-586-0 , 8192114370 , 250-21001 , 12014 , 8933004243 , AFS20 , DY-573 , 1821382010 , 8-08990-741-0 , SG5 , 25171581 , 21552 , 8251626000 , 8-25105-107-0 , SU4700 , 8-25162-693-0 , 8251626930 , 91171942 , DY-578 , 2135 , REA1001 , 0456288 , 97018586 , 213511 , 8990741 , 8251331850 , 25171572 , 25105901 , 8-25105-901-0 , 25176707 , 25171574 , 213502 , 25162693 , 5S3071 , 5300 0886 , AFS22 , 06003981 , 213503 , AFS21 , FE823 , 25162600 , DY578 , 8-25133-185-0 , OS701 , DY579 , 25165120 , 25171573 , 2131167 , 8-25162-753-0 , 8251668160 , 8-94408-151-0 , 0258002014 , DY573 , REA9119 , 213504 , 8-25166-816-0 , 18213-60B00 , AFS33 , 5613959 , 96060174 , AFS81 , 25133185 , 8970185860 , 1377953 , SG122 , OS102 , DY-579 , 25107378 , 21315 , 8990469 , 213500 , 19211437 , 25105107 , 8-25162-600-0 , SU1434 , 8251051070 , 18213-82010 , OS624 , SG12 , 5014780AA , 138-101 , 8-19211-437-0 , 19178953 , 25166169 , FE803

Qty:
$17.62
Delphi Oxygen Sensor  Upstream
  • Oxygen Sensor
  • 12.6in Length
  • Product Attributes:
    • Overall Length: 320.0
    • Sensor Type: Non Heated
    • Wire Quantity: 1
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 2
    • Most jobs typically require 2 of this item.
Brand: Delphi
Position: Upstream
Additional Fitment Information:
Vehicle Submodel Aspiration Fuel Type Position Block Engine CID CC
1987 - Buick Regal Grand National Turbocharged GAS Upstream V 6 Cyl 3.8L 231 3800
Delphi
1998 Buick LeSabre Oxygen Sensor - Rear 6 Cyl 3.8L Delphi

P311-04CA5A9    ES20002  New

SU1295 , 8125872140 , 25312196 , SG277 , 19178922 , 8191789240 , 8-25164-983-0 , 5S3126 , OS229 , DY734 , 138266 , 2344025 , 8253122070 , SU1189 , 5S8134 , AFS141 , 25164983 , REA1010 , 5S8151 , DY-734 , 25312207 , AFS123 , SU1299 , 138752 , 21544 , 138-752 , 12578459 , 25318321 , 8-19178-924-0 , OS1072 , DY731 , 12587214 , AFS116 , 25161130 , FE6085 , 2344087 , 138-266 , 234-4025 , 11170 , 25024340 , DY-776 , 25132207 , 234-4087 , DY776 , 25132196 , 21528 , 138217 , 8251649830 , 8-25312-207-0 , DY-731 , 5S3125 , 19178924 , 5S3119 , 5S3116 , 13444 , 25327815 , AFS97 , 138-217 , SU1087 , 19178747 , 2131681 , OS825 , 8-12587-214-0

Qty:
$54.76
Delphi Oxygen Sensor  Rear
  • Oxygen Sensor
  • 18in Length
  • Product Attributes:
    • Connector Shape: Square
    • Overall Length: 320.0
    • Sensor Type: Heated
    • Wire Quantity: 4
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 4
    • Most jobs typically require 4 of this item.
Brand: Delphi
Position: Rear
Additional Fitment Information:
Vehicle Submodel Engine Designation Aspiration Fuel Type Position Block Engine CID CC
1998 - Buick LeSabre Limited L36 Naturally Aspirated GAS Rear V 6 Cyl 3.8L 231 3800
Delphi
2015 Buick Enclave Oxygen Sensor - Rear 6 Cyl 3.6L Delphi

P311-3A090FC    ES20113  New

5S8156 , 691505 , 21044 , 138-675 , 2344289 , 25024339 , 12603814 , 5S8167 , 8-12578-624-0 , 8-12590-750-0 , SU9602 , 12581346 , 24577303 , 2131143 , 138675 , OS1459 , 21022 , 234-4565 , 8-24577-303-0 , 12586646 , 2133909 , 234-4286 , SG1300 , SU1508 , 12634064 , 2132830 , 234-4818 , 16746 , 15696 , 234-4840 , 5S10069 , 19209805 , 12 59 0750 , 234-4285 , OS2418 , 8125786240 , SG1826 , SU9640 , 2131633 , SU11522 , 12589550 , 5S8139 , 15543 , SG1412 , 2133851 , 8245773030 , 18213-78J10 , 16134 , 2344818 , 16451 , SU9613 , 5S8136 , 12590750 , 5S4283 , 5S8147 , 2344285 , 234-4289 , 12 57 8624 , 5S8174 , 16449 , 2131531 , 15129 , SU9622 , 12597449 , SG706 , 8125907500 , 12578624 , 2133530 , 16938 , 5S4400 , SU9605 , 5S10170 , SU7205 , 21035 , 16828 , 11275 , 234-4344 , OS2133 , 1821378J10 , 2344344 , 12570795 , 15550 , 8192098050 , 12596688 , 12616203 , 8-19209-805-0 , SU9633 , 12590035 , 250-24773 , 234-4294 , 2134191 , 19 20 9805 , REA1167 , 234-4566 , 15894 , 800 21085 , SG1585 , 15434 , 5S5710 , 2132823 , 2133858 , 15449 , SU1489 , 2344259 , REA1885 , 12634085 , 80021085 , 21545 , OS2663 , 12598176 , 15860 , SG937 , SU11623 , 2131574 , 2344840 , 2344286 , 21571

Qty:
$48.60
Delphi Oxygen Sensor  Rear
  • Oxygen Sensor
  • 9in Length
  • Product Attributes:
    • Connector Shape: Square
    • Overall Length: 310.0
    • Sensor Type: Heated
    • Wire Quantity: 4
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 2
    • Most jobs typically require 2 of this item.
Brand: Delphi
Position: Rear
Additional Fitment Information:
Vehicle Submodel Engine Designation Aspiration Fuel Type Position Block Engine CID CC
2015 - Buick Enclave Leather LLT Naturally Aspirated GAS Rear V 6 Cyl 3.6L 217 3564
Delphi
2006 Buick Rainier Oxygen Sensor - Rear 8 Cyl 5.3L Delphi

P311-3A090FC    ES20113  New

5S8156 , 691505 , 21044 , 138-675 , 2344289 , 25024339 , 12603814 , 5S8167 , 8-12578-624-0 , 8-12590-750-0 , SU9602 , 12581346 , 24577303 , 2131143 , 138675 , OS1459 , 21022 , 234-4565 , 8-24577-303-0 , 12586646 , 2133909 , 234-4286 , SG1300 , SU1508 , 12634064 , 2132830 , 234-4818 , 16746 , 15696 , 234-4840 , 5S10069 , 19209805 , 12 59 0750 , 234-4285 , OS2418 , 8125786240 , SG1826 , SU9640 , 2131633 , SU11522 , 12589550 , 5S8139 , 15543 , SG1412 , 2133851 , 8245773030 , 18213-78J10 , 16134 , 2344818 , 16451 , SU9613 , 5S8136 , 12590750 , 5S4283 , 5S8147 , 2344285 , 234-4289 , 12 57 8624 , 5S8174 , 16449 , 2131531 , 15129 , SU9622 , 12597449 , SG706 , 8125907500 , 12578624 , 2133530 , 16938 , 5S4400 , SU9605 , 5S10170 , SU7205 , 21035 , 16828 , 11275 , 234-4344 , OS2133 , 1821378J10 , 2344344 , 12570795 , 15550 , 8192098050 , 12596688 , 12616203 , 8-19209-805-0 , SU9633 , 12590035 , 250-24773 , 234-4294 , 2134191 , 19 20 9805 , REA1167 , 234-4566 , 15894 , 800 21085 , SG1585 , 15434 , 5S5710 , 2132823 , 2133858 , 15449 , SU1489 , 2344259 , REA1885 , 12634085 , 80021085 , 21545 , OS2663 , 12598176 , 15860 , SG937 , SU11623 , 2131574 , 2344840 , 2344286 , 21571

Qty:
$48.60
Delphi Oxygen Sensor  Rear
  • Oxygen Sensor
  • 1st Design 9in Length
  • Product Attributes:
    • Connector Shape: Square
    • Overall Length: 310.0
    • Sensor Type: Heated
    • Wire Quantity: 4
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 2
    • Most jobs typically require 2 of this item.
Brand: Delphi
Position: Rear
Additional Fitment Information:
Vehicle Submodel Engine Designation Aspiration Fuel Type Position Block Engine CID CC
2006 - Buick Rainier CXL LH6 Naturally Aspirated GAS Rear V 8 Cyl 5.3L 325 5328
Delphi
2017 Buick Enclave Oxygen Sensor - Front 6 Cyl 3.6L Delphi

P311-3A090FC    ES20113  New

5S8156 , 691505 , 21044 , 138-675 , 2344289 , 25024339 , 12603814 , 5S8167 , 8-12578-624-0 , 8-12590-750-0 , SU9602 , 12581346 , 24577303 , 2131143 , 138675 , OS1459 , 21022 , 234-4565 , 8-24577-303-0 , 12586646 , 2133909 , 234-4286 , SG1300 , SU1508 , 12634064 , 2132830 , 234-4818 , 16746 , 15696 , 234-4840 , 5S10069 , 19209805 , 12 59 0750 , 234-4285 , OS2418 , 8125786240 , SG1826 , SU9640 , 2131633 , SU11522 , 12589550 , 5S8139 , 15543 , SG1412 , 2133851 , 8245773030 , 18213-78J10 , 16134 , 2344818 , 16451 , SU9613 , 5S8136 , 12590750 , 5S4283 , 5S8147 , 2344285 , 234-4289 , 12 57 8624 , 5S8174 , 16449 , 2131531 , 15129 , SU9622 , 12597449 , SG706 , 8125907500 , 12578624 , 2133530 , 16938 , 5S4400 , SU9605 , 5S10170 , SU7205 , 21035 , 16828 , 11275 , 234-4344 , OS2133 , 1821378J10 , 2344344 , 12570795 , 15550 , 8192098050 , 12596688 , 12616203 , 8-19209-805-0 , SU9633 , 12590035 , 250-24773 , 234-4294 , 2134191 , 19 20 9805 , REA1167 , 234-4566 , 15894 , 800 21085 , SG1585 , 15434 , 5S5710 , 2132823 , 2133858 , 15449 , SU1489 , 2344259 , REA1885 , 12634085 , 80021085 , 21545 , OS2663 , 12598176 , 15860 , SG937 , SU11623 , 2131574 , 2344840 , 2344286 , 21571

Qty:
$48.60
Delphi Oxygen Sensor  Front
  • Oxygen Sensor
  • 9in Length
  • Product Attributes:
    • Connector Shape: Square
    • Overall Length: 310.0
    • Sensor Type: Heated
    • Wire Quantity: 4
  • OE connectors and wire lengths within 3 inches of OE specifications; Unique sensor coatings to resist contamination; Long lasting reliable operation.
  • Suggested Purchase Quantity: 2
    • Most jobs typically require 2 of this item.
Brand: Delphi
Position: Front
Additional Fitment Information:
Vehicle Submodel Engine Designation Aspiration Fuel Type Position Block Engine CID CC
2017 - Buick Enclave Premium LLT Naturally Aspirated GAS Front V 6 Cyl 3.6L 217 3564
Denso
2003 Buick Rendezvous Oxygen Sensor - Upstream 6 Cyl 3.4L Denso - Universal

P311-3D20ED7    234-4209  New

Qty:
$45.51
Denso Oxygen Sensor  Upstream
  • Oxygen Sensor 4 Wire, Universal, Heated, Wire Length: 11.77
  • ; O.E. Quality Universal Replacement Sensor
  • Universal
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 4
    • Wiring Harness Length: 11.77
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Upstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
2003 - Buick Rendezvous Upstream V 6 Cyl 3.4L 207 -
Denso
2005 Buick Rendezvous Oxygen Sensor - Downstream 6 Cyl 3.4L Denso - Universal

P311-3D20ED7    234-4209  New

Qty:
$45.51
Denso Oxygen Sensor  Downstream
  • Oxygen Sensor 4 Wire, Universal, Heated, Wire Length: 11.77
  • ; O.E. Quality Universal Replacement Sensor
  • Universal
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 4
    • Wiring Harness Length: 11.77
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Downstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
2005 - Buick Rendezvous Downstream V 6 Cyl 3.4L 207 -
Denso
2005 Buick Rainier Oxygen Sensor - Downstream 8 Cyl 5.3L Denso - Universal

P311-3D20ED7    234-4209  New

Qty:
$45.51
Denso Oxygen Sensor  Downstream
  • Oxygen Sensor 4 Wire, Universal, Heated, Wire Length: 11.77
  • ; O.E. Quality Universal Replacement Sensor
  • Universal
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 4
    • Wiring Harness Length: 11.77
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Downstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
2005 - Buick Rainier Downstream V 8 Cyl 5.3L 325 5328
Denso
1983 Buick Century Oxygen Sensor - Upstream 6 Cyl 2.8L Denso - OE Style

P311-2D6878D    234-1001  New

213-631 , AFS22 , 12013 , 12014 , 5014780AA , 1821360B00 , 21002 , 1821364B00 , 93232414 , AFS81 , 19211437 , SG5 , 25176707 , AFS20 , 213-1165 , 93322207 , 53000886 , OS700 , AFS21 , OS102 , 75-1504 , ES10966 , 06003981 , OS624 , 213-15 , AFS33 , 213-502

Qty:
$15.06
Denso Oxygen Sensor  Upstream
  • Oxygen Sensor 1 Wire, Direct Fit, Unheated, Wire Length: 14.57
  • ; O.E. Quality Replacement Sensor
  • OE Style
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Non Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 1
    • Wiring Harness Length: 14.57
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Upstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
1983 - Buick Century Upstream V 6 Cyl 2.8L 173 -
Denso
1993 Buick Regal Oxygen Sensor - Upstream 6 Cyl 3.1L Denso - OE Style

P311-2D6878D    234-1001  New

213-631 , AFS22 , 12013 , 12014 , 5014780AA , 1821360B00 , 21002 , 1821364B00 , 93232414 , AFS81 , 19211437 , SG5 , 25176707 , AFS20 , 213-1165 , 93322207 , 53000886 , OS700 , AFS21 , OS102 , 75-1504 , ES10966 , 06003981 , OS624 , 213-15 , AFS33 , 213-502

Qty:
$15.06
Denso Oxygen Sensor  Upstream
  • Oxygen Sensor 1 Wire, Direct Fit, Unheated, Wire Length: 14.57
  • ; Excludes Calif. O.E. Quality Replacement Sensor
  • OE Style
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Non Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 1
    • Wiring Harness Length: 14.57
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Upstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
1993 - Buick Regal Upstream V 6 Cyl 3.1L 189 -
Denso
2008 Buick Lucerne Oxygen Sensor - Upstream 6 Cyl 3.8L Denso - Universal

P311-3D20ED7    234-4209  New

Qty:
$45.51
Denso Oxygen Sensor  Upstream
  • Oxygen Sensor 4 Wire, Universal, Heated, Wire Length: 11.77
  • ; Excludes Calif. O.E. Quality Universal Replacement Sensor
  • Universal
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 4
    • Wiring Harness Length: 11.77
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Upstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
2008 - Buick Lucerne Upstream V 6 Cyl 3.8L 231 3800
Denso
2004 Buick Rainier Oxygen Sensor - Upstream 8 Cyl 5.3L Denso - Universal

P311-3D20ED7    234-4209  New

Qty:
$45.51
Denso Oxygen Sensor  Upstream
  • Oxygen Sensor 4 Wire, Universal, Heated, Wire Length: 11.77
  • ; O.E. Quality Universal Replacement Sensor
  • Universal
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 4
    • Wiring Harness Length: 11.77
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Upstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
2004 - Buick Rainier Upstream V 8 Cyl 5.3L 325 5328
Denso
1993 Buick LeSabre Oxygen Sensor - Upstream 6 Cyl 3.8L Denso - OE Style

P311-2D6878D    234-1001  New

213-631 , AFS22 , 12013 , 12014 , 5014780AA , 1821360B00 , 21002 , 1821364B00 , 93232414 , AFS81 , 19211437 , SG5 , 25176707 , AFS20 , 213-1165 , 93322207 , 53000886 , OS700 , AFS21 , OS102 , 75-1504 , ES10966 , 06003981 , OS624 , 213-15 , AFS33 , 213-502

Qty:
$15.06
Denso Oxygen Sensor  Upstream
  • Oxygen Sensor 1 Wire, Direct Fit, Unheated, Wire Length: 14.57
  • ; 1 Lead Sensor O.E. Quality Replacement Sensor
  • OE Style
  • Product Attributes:
    • Mounting Type: Threaded
    • Sensor Type: Non Heated
    • Thread Diameter: 0.708
    • Wire Quantity: 1
    • Wiring Harness Length: 14.57
  • DENSO Oxygen Sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Position: Upstream
Additional Fitment Information:
Vehicle Position Block Engine CID CC
1993 - Buick LeSabre Upstream V 6 Cyl 3.8L 231 3800
ACDelco
2005 Buick Rainier Oxygen Sensor 6 Cyl 4.2L ACDelco

P311-4F8C116    W0133-1763262  New

Qty:
$100.92
ACDelco Oxygen Sensor
  • This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
  • Genuine GM
Brand: ACDelco
Additional Fitment Information:
Vehicle Block Engine CID CC
2005 - Buick Rainier L 6 Cyl 4.2L 256 -
ACDelco
2008 Buick Enclave Oxygen Sensor ACDelco

P311-464E8DE    W0133-1866265  New

Qty:
$110.36
ACDelco Oxygen Sensor
  • This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
  • Genuine GM
Brand: ACDelco
Additional Fitment Information:
Vehicle
2008 - Buick Enclave
ACDelco
2000 Buick Regal Oxygen Sensor ACDelco

P311-47C893B    W0133-1833385  New

Qty:
$73.89
ACDelco Oxygen Sensor
  • This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
  • Genuine GM
Brand: ACDelco
Additional Fitment Information:
Vehicle
2000 - Buick Regal
ACDelco
2006 Buick Rainier Oxygen Sensor 8 Cyl 5.3L ACDelco

P311-2DAD541    W0133-1951093  New

Qty:
$114.03
ACDelco Oxygen Sensor
  • This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
  • Genuine GM
  • ; with 1st Design Sensor
    (Stamped 12590750 or 12600893, Square Connector)
Brand: ACDelco
Additional Fitment Information:
Vehicle Block Engine CID CC
2006 - Buick Rainier V 8 Cyl 5.3L 325 5328
ACDelco
2005 Buick LaCrosse Oxygen Sensor 6 Cyl 3.8L ACDelco

P311-51BFA70    W0133-1950724  New

Qty:
$94.79
ACDelco Oxygen Sensor
  • This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
  • Genuine GM
Brand: ACDelco
Additional Fitment Information:
Vehicle Block Engine CID CC
2005 - Buick LaCrosse V 6 Cyl 3.8L 231 3800

Latest Buick Repair and O2 Sensor Installation Advice

CarJunky AutoAdvice

2005 Buick Century codes p1404 and p520

Showing 3 out of 4 Posts | Show 1 Hidden Posts
Question From robertmt on 2005 Buick Century codes p1404 and p520

Please be patient while I explain what I have done with this vehicle. I got a service engine light about a month ago which pointed to the EGR valve. I changed the valve and the light went off for a time. Then I get the light again, I have a code p0171 suggesting O2 sensor. I changed the O2 sensor on the exhaust manifold to no avail. Ordered and replaced the downstream O2 sensor near the Cat and all codes were gone. Success! For a day.

I then find that the water pump is leaking so to gain easy access to the pump, I reposition a large wiring harness and pushed it up toward the windshield while I replaced the pump. After that, everything is fine again, and today we have a strong smell of fuel from under the hood, along with codes P1404 AND P0520. It seemed I may have disturbed some connections somewhere, since these two codes do not seem to be related, but cannot find anything out of place.

After the fuel odor dissipates, the engine runs great, no hesitation, no stalling no shaking. Just the engine light on!

Thanks in advance for any ideas!

Response From Hammer Time Top Rated Answer

Then I get the light again, I have a code p0171 suggesting O2 sensor. I changed the O2 sensor on the exhaust manifold to no avail. Ordered and replaced the downstream O2 sensor near the Cat and all codes were gone. Success! For a day.

You're dreaming if you're expecting a downsteam sensor to resolve a P0171. It has absolutely nothing to do with that sensor. It's a lean code.

The P1404 could be due to carbon chunks being broken off and getting caught in the valve.

The P0520 is a problem with the oil pressure sensor circuit.

Response From robertmt

Well that was my understanding too, but out of desperation I changed the downstream O2 sensor and the light went off!

Thanks for the reply.

Response From Hammer Time

Changing the sensor didn't cause the light to go out. That sensor has one purpose and one purpose only and that is to monitor the efficiency of the Catalyst. It has no relationship to fuel mixture.

Sudden gas consumption on a 3.8L Buick engine

Showing 2 out of 4 Posts | Show 2 Hidden Posts
Question From warrenoie on Sudden gas consumption on a 3.8L Buick engine

93 Buick Regal started using quite a bit of gas. Changed catylatic converter and air filter. Also cleaned the MAP sensor. Helped but still using excessive gas for a 3.8L engine. Any ideas. Thanks

Response From Tom Greenleaf

Questions: Is it running properly now? How are you monitoring fuel consumption and what was it before and now?

T

Response From warrenoie

After I changed the plugs and fuel filter it seems to be back to normal. This is After I changed the catylatic converter (which was plugged) and put in the new air filter which was in need of being changed too! The poor old girl was in bad need of some tender lovin care but after being brought back up to date and an oil change too, everything seems to be in good working order now.

Response From Guest Top Rated Answer

WHAT ABOUT YOUR O2 SENSOR

2001 Buick Cat/o2 sensor contamination P0420

Showing 7 out of 19 Posts | Show 12 Hidden Posts
Question From terasys on 2001 Buick Cat/o2 sensor contamination P0420

Well. My car:

2001 Buick LeSabre Custom 3.8 160k miles

has the infamous p0420 code. I have noticed decreased fuel efficiency (on average the last week its around 12 mpg.... yeah..)

I know the code points to the Cat not working efficiently or as it should, but I wanted to test the upstream o2 sensor first because that could explain the bad gas mileage.

It passed inspection last year only because the mechanic cleared the code and then let it slide. I decided to test the upstream o2 sensor first before shelling out 100's.

It seemed to be working fine: went up to 0.9 volts under high temps and went back down to under 0.1 volts very quickly in around 1-2 seconds. Seems pretty normal. BUT, the head of the o2 sensor was chalky white. Which is a tell tale sign of silicone contamination. I suppose this could lead to my cat being inefficient and thusly throwing the code.

The problem is: I read online that coolant has silicone in it. Last year I got a coolant flush and got it filled up. Since then, my coolant reservoir has gone from about 1/3-1/2 full to pretty much empty right now. Does it usually just go away like that? Could it be leaking into the engine somehow? Could this be put on the mechanic's (Sears..psh) fault? Did they mess it up somehow and make a leak?

I also have a pretty good (bad) power steering leak. I need to put a new bottle in about every 2 weeks or so. I ALSO have a slight oil leak too. The guy who owned the car before me said it just burns up as it drips off. I need to add a quart of oil every 3-4 months MAYBE. I haven't since probably last summer and it needed 2 quarts when I recently did add some.

The bottom of my car has a pretty decent layer of black tar/oil coating everything. including almost all of the hoses near the front axle. My car will leak (which I believe is power steering fluid) 100% of the time. No matter if I let it sit for an hour or 2 seconds. it is constantly dripping.

Any ideas?

Should I test the downstream o2 sensor? (pain in the ass)

Thanks!

Response From Hammer Time

Some of what you are saying has a little truth and most of it is out in left field.

Coolant doesn't contain silicone, some of it contains silicates but not Dexcool which is what you should have in there.

You have a bad Cat. The PO420 rarely indicates anything but a bad Cat because of the criteria it takes to set that code. The white on the 0/2 sensor doesn't mean anything bad and that's pretty normal. You're way off on how the 0/2 is supposed to operate also. I don't know where your coolant is going but you should be able to find out with some careful pressure testing. That particular engine has a known problem with intake manifold deterioration causing coolant to leak into a vacuum chamber under it. There is a TSB on that.

Response From terasys

Link deleted.................. is where I found the information about the o2 sensors colors.

I wanted to save so money so what I was going to do was buy a cat online (they run from (what i saw) around 90-300) and I know a mechanic who will install one for about 75 bucks.

will that clear the code? Should I get him to install new o2 sensors as well? Or should I just buy a new upstream? Because honestly I went through 4 gallons (16 dollars) of gas going about 45 miles.

What is a TSB? Can you link this?

Response From Hammer Time

We don't allow links on the site but I will post an image of the TSB. They don't list your year but it's still possible. As I said, you need to pressure test.

I wouldn't even attempt to buy a converter online. Just go to a custom exhaust shop and they will install one for likely less money that you can even buy one. My shop gets $180 installed for a universal cat.

As far as the 0/2s, don't be too concerned with the color as much as how they operate. Sensor will deteriorate over time so changing them is never a bad idea. The upstream is the only one that has anything to do with fuel mixture. The downstream is a Cat monitor only.



Response From terasys

Okay awesome.

I figured it would be like 400-600 for something like that.

I will call a couple places and see what the prices look like.

Thanks for that pic but where do I find more information? Just googling?

And: I read many reviews online that a new cat sometimes does not clear the code. Any reason why it wouldn't in my case? (Your best guess obviously).
Thanks again!

Response From Hammer Time

I have seen that code dozens of times and only once did a new Cat not resolve it and in that case, the exhaust pipe had a crack in it just ahead of the cat and the oxygen was confusing the sensors.

Response From terasys

How long will it take to have the code come back on after clearing it? Its been over 25 miles since I cleared it and it has not come back yet..

Response From Hammer Time

It takes a while because the computer has to see very specific criteria and it may have to see it more than once.

Here's some reading for you on that code



CIRCUIT DESCRIPTION
In order to control emissions of Hydrocarbons (HC) , Carbon Monoxide (CO) , and Oxides Of Nitrogen (NOx) , a three-way catalytic converter is used. The catalyst within the converter promotes a chemical reaction which oxidizes the HC and CO present in the exhaust gas, converting them into harmless water vapor and carbon dioxide. The catalyst also reduces NOx, converting it to nitrogen. The converter also has the ability to store excess oxygen and release the stored oxygen to promote these reactions. This Oxygen Storage Capacity (OSC) is a measurement of the catalyst's ability to control emissions. The Powertrain Control Module (PCM) monitors this process using a Heated Oxygen Sensor (HO2S) located in the exhaust stream past the 3-way converter. When the catalyst is functioning properly, the HO2S 2 is slow to respond to a large change in the HO2S 1 signal. When the HO2S 2 responds quickly to a large change in the HO2S 1 signal, the OSC and efficiency of the catalyst is considered to be bad and the MIL will be illuminated if subsequent tests also indicate a failure.

CONDITIONS FOR RUNNING THE DTC

  • Meet he conditions for engine warm up. Use the scan tool catalyst data list in order to verify the following.
  • DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0130, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0171, P0172, P0201-206, P0300, P0336, P0341, P0401, P0403, P0404, P0405, P0410, P0412, P0418, P0440, P0442, P0443, P0446, P0449, P0502, P0503, P0506, P0507, P1133, P1134, P1336, P1351, P1352, P1361, P1374, or P1441 are not set.
  • The engine has been running more than 10 minutes.
  • The Engine Coolant Temperature (ECT) is above 70°C(158°F) and below 124°C (255°F).
  • The Barometric Pressure (BARO) is above 75 kPa.
  • The vehicle is in Closed Loop.
  • The Intake Air Temperature (IAT) is above - 20°C (-4°F) and less than 100°C (212°F).
  • The battery voltage above 10.7 volts
  • Warm up the catalyst.
  • Fully open the hood.
  • Place the transmission in park (automatic) or neutral (manual).
  • Set the parking brake.
  • Press and hold the service brake.
  • Each time the engine is started, the diagnostic can run up to 18 times. After the 10-minute run time and before the diagnostic runs the first time, the engine must run an additional 5 minutes between 1500-2500 RPM.

  • For any additional tests on the same key cycle, the engine speed must be between 1500-2500 RPM for 1 minute.
  • In order to activate the diagnostic return the vehicle to idle and put the vehicle in drive, or depress the clutch for a manual transmission.
  • Test the catalyst.
  • Place the transmission in drive (automatic) or neutral (for manuals with clutch depress).
  • VIN K California Emissions- Within 60 seconds the air fuel ratio will go rich below 14.1 for up to 6 seconds , then it may go lean above 15.3 for up to 8 seconds.
  • VIN K FED Emissions-Within 60 seconds the air fuel ratio will go lean above 15.3 for up to 6 seconds , then may go rich below 14.1 for up to 7 seconds.
  • VIN 1-With in 60 seconds the air fuel ratio will go rich below 14.1 for up to 7 seconds , then it may go lean above 15.3 for up to 9 seconds.
  • Check if DTC P0420 has passed or failed this key cycle using the scan tool.

  • CONDITIONS FOR SETTING THE DTC
    The PCM determines that the catalyst's oxygen storage capacity is below an acceptable threshold.

    ACTION TAKEN WHEN THE DTC SETS
  • The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
  • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

  • CONDITIONS FOR CLEARING THE MIL/DTC
  • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
  • A current DTC "Last Test Failed" clears when the diagnostic runs and passes.
  • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
  • Use a scan tool in order to clear the MIL and the DTC.

  • DIAGNOSTIC AIDS
    Check for the following conditions:
  • The PCM will not enable the catalyst test until following conditions are met:
  • The engine speed is plus or minus 100 RPM from the desired idle.
  • The Throttle Position (TP) is 0.0 percent.
  • The short term integrator is between -20 percent and +20 percent.
  • The catalyst test will abort if the vehicle falls outside the conditions listed below while the test is running:
  • The engine speed is plus or minus 125 RPM from desired idle.
  • The Throttle Position (TP) is 0.0 percent.
  • Short term integrator is between -20 percent and +20 percent.
  • The catalyst test may abort due to a change in engine load, for example, from the A/C or from the coolant fan. If this condition occurs, use the scan tool in order to force the cooling fans ON, and return to Step 2 in the table.

  • IMPORTANT: When using the scan tool to force the cooling fans on use the next list and previous list soft keys to enter the catalyst data list. If the catalyst data list is not entered this way the cooling fan control will be canceled.

  • More than 6 tests may have to be attempted in order to get 6 completed tests. An aborted test counts as an attempted test. The number of attempt tests is limited to 18 per key cycle.

  • After returning to an idle the HO2S 1 signal may stay rich or lean for several seconds causing the test to be delayed.
  • A faulty connection at PCM-Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. Use a corresponding mating terminal to test for correct terminal tension.
  • A damaged harness-Inspect the wiring harness for damage. If the harness appears to be OK, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the display will indicate the location of the fault.

  • Response From terasys

    Oh.. I see.

    It came on tonight actually. After driving a total of 30 miles. but I didn't know it had to be specific criteria like that.

    Thanks anyway. I got an appointment on 5/30 as supposedly the best auto place in the area. His appointments can take up to 2 weeks because so many people go to his place. Supposedly he also does not charge much.

    Hopefully it works out okay

    Response From Hammer Time Top Rated Answer

    You're not looking for the best repair shop in town. You're looking for an exhaust specialty shop. General repair shops are not equipped for custom exhaust and will be more expensive.

    Response From terasys

    The closest thing to an exhaust shop near me is Monro.

    Are they okay?

    I believe I have heard mixed things about them.

    Edit: On their website they are offering a 30% off muffler/catalytic converter sale.

    Will that be pretty cheap? I will call tomorrow.

    Thanks again

    Response From Hammer Time

    It doesn't matter who they are as long as they have a pipe bender on-site. That would mean that they are in the business of making custom exhaust and have the toola and ability to do what's needed at a reasonable price. If they do not make custom exhaust on a regular basis, they cannot be competitive with the price. Midas may be the exception to that. They are always kinda expensive.

    Response From terasys

    Well.. I called one Monro and they said they cannot give me an estimate so I made an appointment on Tuesday morning for them to check it out.

    So I called another Monro and he calculated the cost to be 465 for a universal and 700 for an OEM.

    yeah.... I will keep looking. That is ridiculous

    Edit: Should I be looking for custom exhaust shops?

    Response From Hammer Time

    Edit: Should I be looking for custom exhaust shops?

    Didn't I say that 3 times?

    Response From terasys

    You said "exhaust specialty" shops.

    I have no idea if that is the same as custom? How does custom which includes like stainless steel compare to just having exhaust as a specialty? I guess it is clearer to trained eyes..

    Response From Hammer Time

    OH, come on............


    Exhaust specialty...................... to mean specialize in exhaust repair.



    Maybe you recall reading this....

    Just go to a custom exhaust shop and they will install one for likely less money that you can even buy one. My shop gets $180 installed for a universal cat.

    Response From terasys

    Hahaha Okay okay okay. I got it. I got a couple places lined up.

    Response From Tom Greenleaf

    I have no specific problem with any chain. If they are having a sale go for it. Best will always be OE stuff for exhaust items IMO but if it works and a bargain can't argue,

    T
    (sorry for spammer being removed now)

    Response From terasys

    Well the thing is i Have multiple issues. I want all the leaks fixed as well. I have an appointment on the 30th to get it checked out. If getting a new cat installed is around 200-250 ill get it done. If i can find a better place in the area, ill do it there.

    I havent seemed to find a custom exhaust place.

    p1406 and p0135

    Showing 2 out of 10 Posts | Show 8 Hidden Posts
    Question From monty102 on p1406 and p0135

    I got a 1997 Buick lesabre with a new egr on it and it is throwing a p1406 egr pindle position code and a p0135 bad upstream heater code.
    I ordered a new sg454 o2 sensor and I will put it on this week. Should that fix the problem?

    Does anyone know if the egr ground for the pindle signal to that pcm is the same as the ground for the heater on the o2 sensor. I'm thinking that may be the reason I got the p1406 code but I don't know for sure.

    Does anyone know if the egr pindle position has to be relearned. I do not have a tech 2 scanner to command the pcm to do relearning but I have
    noted that it can be accomplished without the tech 2 scanner by disconnecting the wiring harness on the egr. turning the switch on and scanning for the codes that are thrown and right after you clear them turn the ignition off and then reattach the egr harness and this will cause the pcm to relearn the egr pindle position
    of the egr.


    links from other forum removed.

    Response From Hammer Time

    Does anyone know if the egr ground for the pindle signal to that pcm is the same as the ground for the heater on the o2 sensor. I'm thinking that may be the reason I got the p1406 code but I don't know for sure.

    Definitely not. The ground is the control wire for the EGR connected to the PCM. Nothing to do with an 0/2 heater. The EGR has no relearn process. You most likely have a bad EGR valve.

    Response From monty102 Top Rated Answer

    The relearn process is mentioned on this post: Unfortunately The link got deleted but you can google it if you want.

    Also the wiring diagram on autozone for this vehicle shows that
    the egr grounds to the the sensor ground. It doesn't state what sensor but since its wiring is located next to the o2 sensor I suspected that meant it was that o2 senor that grounded the egr

    The egr in the vehicle that is throwing the code is the same egr that originally threw the code. I removed it after it threw the code and repalced it with my 1999 lesabre egr which was not throwing a code. I put the 1997 egr on the 1999 lesabre and I have driven it 90 miles with no codes.

    So, I decided to look at the wiring diagram to see why the o2 sensor and the egr seem to throw the codes on the 1997 buick at the same time because it appears the egr itself is
    not faulty. That is when i noted on the autozone wiring diagram that the egr and the o2 sensor "may" have the same ground. I believe the ground on the o2 sensor
    is in the heater circuit and i believe that is what the p0135 code relates to. The p1406 code is refers to the pindle position of the egr and that ground is the ground
    that I suspect goes to the o2 wiring harness.


    Link removed, not allowed

    Response From Hammer Time

    That was just some guy's opinion.

    There is nothing to learn. the EGR feeds position info back to the PCM and the PCM commands it's movement. The PCM is hard programmed to EGR operation.









    The linear EGR valve is designed to accurately supply EGR to an engine independent of intake manifold vacuum. The valve controls EGR flow from the exhaust to the intake manifold through an orifice with a PCM controlled pintle. During operation, the PCM controls pintle position by monitoring the pintle position feedback signal. The feedback signal can be monitored with a scan tool as ACTUAL EGR P0S. ACTUAL EGR P0S should always be near the commanded EGR position ( DESIRED EGR P0S).

    The PCM uses information from the following sensors to control the pintle position:

  • Engine Coolant Temperature (ECT) sensor.
  • Throttle Position (TP) sensor.
  • Mass Air Flow (MAF).

  • The linear EGR valve is usually activated under the following conditions:
  • Warm engine operation
  • Above idle speed

  • LEGEND IMAGE # 3
    1. Linear EGR Valve
    2. Exhaust Gas
    3. To Cylinders
    4. Pintle

    Response From Hammer Time

    My bet on this is the EGR has built up carbon under the pintle, not allowing it to return to fully seated position. The cure is new EGR.


    More info from the service manual.


    The Exhaust Gas Recirculation (EGR) system is used to lower Oxides of Nitrogen (NOx) emission levels caused by high combustion temperature. It does this by decreasing combustion temperature.

    The main element of the system is the linear EGR valve. The EGR valve feeds small amounts of exhaust gas back into the combustion chamber. With the fuel/air mixture diluted by the exhaust gases, combustion temperatures are reduced.

    The valve controls EGR flow from the exhaust to the intake manifold through an orifice with a PCM controlled pintle. During operation, the PCM controls pintle position by monitoring the pintle position feedback signal. If a problem with the EGR system will not allow the PCM to control pintle position properly, DTC P1406 should set. The PCM also tests for EGR flow; if incorrect flow is detected, DTC P0401 should set.

    Response From monty102

    I've found that the mass air flow sensor can make the egr throw codes too. When it does the maf throws no code. Your
    response seems to indicate that the maf could be my problem as the egr itself are clear of carbon and don't throw codes
    on the other buick I have put both of them on. They just throw codes on the 1997 buck that is why I was looking at the o2
    sensor as the problem. I could be wrong. Since the maf is 45 bucks I hate to buy one without knowing it will fix the p1406 code
    problem. Thks for your interest..... Kinda like trying to figure out the recipe for KFC chicken.....

    Response From Hammer Time

    I'm not going to waste a whole bunch of effort debating someone that is relying on the Internet to educate themselves.

    I'm telling you right now. There is no EGR programming and there is no way a MAF will set a P1406. Do whatever you want. It's your money to waste.

    Response From monty102

    Guess you are having a bad day. Sorry you read my post. I'll go it my on.

    What i told you were intended only to just explain my situation and what I had learned trying to fix my problem. I am sorry if you

    feel you are wasting your time checking anything out. The wiring diagram from autozone is all had to

    go by to conclude the the ground for the O2 sensor is the same as the egr.

    Pls do not respond back as I do not need you help if it ruins you day and makes you feel as though you are debating someone.

    Response From Hammer Time

    No problem. Go waste some money.

    Response From nickwarner

    If you have a pile of buicks behind your trailer and only rely on Autodeath for information, good luck fixing this. You were given good advice and instead of choosing to investigate the issue wanted to explain it your own way and find a way to never buy parts. Welcome to the real world (which does suck) you actually have to replace crap parts over a decade old with new ones, not other crap parts over a decade old. If you won't do that and won't listen to anyone other than some idiot kid at a parts counter popping a zit because he tells you what you want to hear then your car will run like crap and you'll spend more money in parts you didn't need than what you would to find the right one you did. Best of luck.