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Best Selling Genuine Mitsubishi Oxygen Sensors

  • We Stock the following top leading brands, including Denso
  • Constantly Updated Inventory of Mitsubishi Replacement Oxygen Sensor Parts

We stock Oxygen Sensor parts for most Mitsubishi models, including 3000GT, Diamante, Eclipse, Galant, Lancer, Mirage, Montero, Montero Sport, Outlander, Outlander Sport.

Denso
Qty:
$21.22
Denso Oxygen Sensor  Upstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 15.75
  • OE Style
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
2007 - Mitsubishi Raider V - 226 Upstream Left
Denso
Qty:
$21.22
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 15.75
  • OE Style
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
2006 - Mitsubishi Raider V - 226 Downstream Right
Denso
Qty:
$21.22
Denso Oxygen Sensor  Upstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 15.75
  • O.E. Quality Replacement Sensor
  • OE Style
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
2007 - Mitsubishi Raider V - 226 Upstream Left
Denso
Qty:
$21.22
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 15.75
  • O.E. Quality Replacement Sensor
  • OE Style
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
2006 - Mitsubishi Raider V - 226 Downstream Right
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Engine VIN Position
1989 - Mitsubishi Galant L 1997 122 R Upstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
1993 - Mitsubishi Expo L 2351 - Downstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
1997 - Mitsubishi Diamante V 3497 215 Downstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
1997 - Mitsubishi Diamante V 3497 215 Upstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Aspiration Block CC CID Position
1994 - Mitsubishi 3000GT Turbocharged V 2972 181 Downstream Right
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Aspiration Block CC CID Position
1994 - Mitsubishi 3000GT Naturally Aspirated V 2972 181 Downstream Left
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream Right
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Aspiration Block CC CID Position
1993 - Mitsubishi 3000GT Turbocharged V 2972 181 Upstream Right
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream Left
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Aspiration Block CC CID Position
1993 - Mitsubishi 3000GT Turbocharged V 2972 181 Upstream Left
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream Front
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
2001 - Mitsubishi Eclipse V 2972 181 Downstream Front
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream Rear
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
2001 - Mitsubishi Eclipse V 2972 181 Downstream Rear
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • O.E. Quality Universal Replacement Sensor
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Engine VIN Position
1989 - Mitsubishi Galant L 1997 122 R Upstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • O.E. Quality Universal Replacement Sensor
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
1994 - Mitsubishi Expo L 2351 - Downstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • O.E. Quality Universal Replacement Sensor
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
1997 - Mitsubishi Diamante V 3497 215 Downstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Calif. O.E. Quality Universal Replacement Sensor
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Position
1993 - Mitsubishi Expo L 2351 - Upstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Upstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Excludes Calif. O.E. Quality Universal Replacement Sensor
  • Universal
  • 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
Additional Fitment Information:
Vehicle Aspiration Block CC CID Position
1994 - Mitsubishi 3000GT Naturally Aspirated V 2972 181 Upstream
Denso
Qty:
$36.72
Denso Oxygen Sensor  Downstream
  • 4 Wire, Universal, Heated, Wire Length: 11.77
  • Excludes Calif. O.E. Quality Universal Replacement Sensor
  • Universal
  • 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
Additional Fitment Information:
Vehicle Block CC CID Drive Type Position
1995 - Mitsubishi Expo L 2351 - FWD Downstream

Latest Mitsubishi Repair and Oxygen Sensor Installation Advice

CarJunky AutoAdvice

Oxygen Sensors: manufacturer versus universal

Showing 4 out of 4 Posts
Question From BKL on Oxygen Sensors: manufacturer versus universal

I have 2003 Mitsubishi Galant ES V6. OBD gave P0135 trouble code (Oxygen Sensor heater circuit problem or such). Dealer quoted incredible price for sensor (recommended to replace both, there is pair of them for each side of engine).
Online can find variety of sensors from Universal to Direct Fit, much cheaper.
Question: are those sensors OK?

Response From DanD Top Rated Answer

I agree; it is a crapshoot with after market components.
This is my thinking on electronic after market items. If whomever reproduced/cloned this piece did so with a “first” design it should work? But if this component and the original manufacturer found a fault in it (first design) and replaced with a second, then you’re screwed. Nothing wrong with the after market’s clone but it just does not work because of an oops. After market isn’t going to recall their item and legally don’t have to unless it is a safety issue.

Dan.

Response From BKL

Thanks way2old!

Anyone else had experience with aftermarket oxygen sensors?

Appreciate!

Response From way2old

I have had both good and bad experiences with aftermarket sensors. Guess it is a crap shoot. Usually if you can find a name brand, they last longer than the generic. So it is your call. Might last 10 years or 10 days. Good luck. Maybe some of the independant owners will help you more on this. They usually use more aftermarket than we do.

Location of OBD1 connector 1995 Mitsubishi Diamante Stationwagon

Showing 2 out of 2 Posts
Question From GeeJay on Location of OBD1 connector 1995 Mitsubishi Diamante Stationwagon

We just purchased an autoxray 2000 from JCWhitney which is suppose to be for a 1995 Mitsubishi Diamante Stationwagon. We cannot find the connector on the car and we cannot configure the reader. Our vehicle is certified OBD1 as stated under the hood. What is the deal on this? Our engine light came on yesterday. We suspect the oxygen sensor but would really like to know if this reader is going to work on our vehicle. Thanks for any help.

Response From dave284 Top Rated Answer

under hood, midway the firewall closer driverside

MITSUBISHI GALANT 92 MPI Idling Problem

Showing 3 out of 3 Posts
Question From optimistic26 on MITSUBISHI GALANT 92 MPI Idling Problem

Hi,

I have a 1992 model Mitsubishi Galant Super Saloon MPI with a 2.0 liter ECI engine. I'm having problems with its idling. It is erratic and goes up and down reading arounf 1500-2000 on rpm. I tried removing the plug on the oxygen sensor, idling went fine, but I guess this isn't good for the engine. I hope you can shed light to my problem . I would appreciate if you can give me advises. Is there a problem with the servo control? cause I just replace it.


CARL

Response From DanD

Sorry I’m not familiar with the Galant; I don’t think I’ve ever had one in the shop yet.
Dan.

Response From Tom Greenleaf Top Rated Answer

I don't know that car either but you can rule out vacuum leaks and some cruddy looking electrical connections. It's a 1992 and some stuff will happen. You can check for unseen vac leaks with carb cleaner (cooler engine is safer) and spray at subject areas. Stay away from hot items like the exhaust parts and if the idle changes there's something there to check out or fix. T

1993 Eclipse Mystery

Showing 3 out of 4 Posts | Show 1 Hidden Posts
Question From nrd on 1993 Eclipse Mystery

Hi guys (and girls?)

I have a 1993 Mitsubishi Eclipse that has what I think is a bit above average white smoke from the tail pipe, which does go away after about 20 mins of driving (its currently bellow zero here)

I have been keeping an eye on my coolant levels and they are fine staying at a constant level (the reserve at least and when I checked last the coolant levels looked good under the cap), the reservoir doesnt bubble and the colour is blue (as it should be). There is no milkshake looking oil. Nothing around the oil fill cap. No engine over heating either

on top of this I do have Idle Surge, whilst moving with my foot fully on the clutch/out of gear the revs will climb between 1000 and 1700 up and down UNTIL I come to a stand still, then it settles at a normal idle position.

I should point out the exhaust was a cowboy job by previos owner that I have fixed for now, but there are about two hole in it still, and the guy that did it for us mentioned something about the cat. converter maybe need replacing soon.

im confused as to what this is.
I have some valve cleaning solution to put into the petrol, You think its worth giving that a shot?

Cheers

Neal

Response From Loren Champlain Sr

Neal; When the engine is cool, and safe to do so, remove the radiator cap and verify that it is full. Low coolant level can cause the surge at idle. A faulty coolant temp sensor, a vacuum leak, sticky idle control motor, ect. can also cause the surge. As far as the 'white smoke' is concerned....re-tired is right on. A good functioning engine makes it's own water. It is perfectly normal to see condensation steam as a result....even more so in frigid weather. Even more so if the car is driven primarily short distances so that the exhaust system doesn't get hot enough to evaporate the moisture. The exhaust system...if you have an exhaust leak before the Oxygen Sensor, it may be causing a problem as well. The only time a catalytic converter would cause an idle problem would be if it were plugged in which case, you'd have a severe loss of power. Let us know what you find and we can 'go from there'.
Have a great New Years.

Response From nrd Top Rated Answer


Neal; When the engine is cool, and safe to do so, remove the radiator cap and verify that it is full. Low coolant level can cause the surge at idle. A faulty coolant temp sensor, a vacuum leak, sticky idle control motor, ect. can also cause the surge. As far as the 'white smoke' is concerned....re-tired is right on. A good functioning engine makes it's own water. It is perfectly normal to see condensation steam as a result....even more so in frigid weather. Even more so if the car is driven primarily short distances so that the exhaust system doesn't get hot enough to evaporate the moisture. The exhaust system...if you have an exhaust leak before the Oxygen Sensor, it may be causing a problem as well. The only time a catalytic converter would cause an idle problem would be if it were plugged in which case, you'd have a severe loss of power. Let us know what you find and we can 'go from there'.
Have a great New Years.

Hi again,
Thanks for the help here from everyone. I have checked, double checked and checked again the radiator levels. My reservoir is just on the full mark and has been since I topped it up about a month ago. I have read that the idle controll motor CAN stick on the Eclipse, so I might be needing a new one or it to be fixed. Im going to send it to a garage hopefully sometime this month to get the CV joints looked at so will bring it up at the same time.

The smoke issue still persists, im sure its not steam as it lingers a bit longer than normal..but then I have seen a few cars on the road with the same exhaust output...so im not sure still. I cant relax about it.Haha. When i take it to the garage I will mention this first, if its bad news there is no point me fixing with the other things. Thanks again for your help, really appreciated.

Will let you know how it goes.

Neal

Response From re-tired

Sometimes it is hard to tell two different kinds of "white" smoke apart . One is steam ,which will dissapate rather quichly. The other is oil smoke which tends to linger a bit longer .Check tailpipe for water or oil residue.Worn or hardened valve seals will cause smoke for a short time after start up also.

2000 Mitsubishi Montero Sport 3.6L 4WD won't run for more than a few minutes - ??catalytic converter failure??

Showing 3 out of 6 Posts | Show 3 Hidden Posts
Question From jtmill02 on 2000 Mitsubishi Montero Sport 3.6L 4WD won't run for more than a few minutes - ??catalytic converter failure??

upon leaving work on sunday night, got to my 2000 Mitsu Montero Sport 3.6L 4WD and realized i had left my lights on (recurrent bad habit) and the battery was DEAD. had a friend right there who was happy to give a jumpstart. in a hurry to get home, i carelessly crossed the cables. after realizing the problem, i successfully started the car but it quickly died 30 seconds after the cables were disconnected. figured i had fried the alternator and got the car towed to my dealer.

here's where it gets funny. dealer checks it out yesterday and confirmed the alternator was shot as well as the battery. replaced both as well as a couple of fuses that were also blown. but when they started the car and let it idle, after several minutes the engine began to sputter and subsequently stopped running. after sitting for a while, it would start and run fine, but then after a couple more minutes stop. based on the way it was running, the tech felt like it was a problem with blocked exhaust. he removed the oxygen sensor in front of the catalytic converter, which supposedly allowed air to escape and the engine ran fine. replacing the sensor almost immediately killed the engine. this led him to believe the catalytic converter was bad, and that as it got hot it was clogging(swelling?) up, obstructing the exhaust.

some of this was communicated to me over the phone, and my initial impression was that it was just running like normal and somebody was just overly sensitive to some rattle or something. of note, it had been running very well before all this. when i got to the dealer, i pulled the car around from where they had parked it up to the service desk to settle up - it ran great for that brief (~30 second) drive. they explained the above to me and recommended that i leave it with them to get their exhaust guys to replace the part. i still didn't quite understand and decided to take my chances.

everything seemed great for about three or four minutes. then it happened. while idling in traffic just in front of the dealer, the engine stalled and died within 5 seconds. i was able to get it off the road and sat for a couple of minutes. it started back up and i drove in the shoulder for about another 50 yards before it died again. after a couple more minutes, i started it back up.

here's where it got funny again. when i started it for the second time, i decided to floor the accelerator to see what would happen. interestingly enough, by doing this, it would sputter but not die. on the trip back through the auto mall (~1/2 mile) it didn't die again, but would sputter for 20 seconds, creeping along at a very low speed, then surprisingly get full power again for about 10 seconds before starting to sputter again. this pattern went on until i made it back to the dealer.

so as of right now, they are confident in the problem being the catalytic converter but without an explanation of why it failed all of a sudden. it is going to an exhaust shop tomorrow where they will run their own diagnostics before possibly replacing it for around $600.

my concerns are:
- my gut tells me that it's not the catalytic converter, rather something electrical. electrical problems are clearly explainable, and the car was running great prior to my bonehead error. i'm afraid of dropping $600 unnecessarily and then starting all over to find the real problem.

- why would the converter fail?? my understanding is that the converters don't really fail on their own, they have to be fouled by fuel rich exhaust burning hot or by some contaminant. my first thought was that if the electrical were shot, possibly there were some timing or sparking problems that led to fuel rich exhaust doing thermal damage to the catalytic converter. one of the guys gave some BS postulation about the fuel formulation used here in KY and that they have been seeing a ton of failed converters - this might explain a chronic failure, but clearly something has happened since sunday.

- if the catalytic converter is bad due to an unexplainable cause which may or may not still be present, what's to keep if from failing again?

- does a failed catalytic converter actually behave this way? i would think you would have problems as soon as the car is started. the explanation that the converter was getting hot and clogging once the engine had been running doesn't make a lot of sense to me, but i don't really have any knowledge base in this area.

of note, the computer had no error codes at any point during this fiasco. also, i bought the car from this dealer and have dealt with them for 11 years. same service manager, and thus far have never had any problems or felt gouged by them.

any input would be greatly appreciated.

thanks in advance,
jason

Response From Discretesignals Top Rated Answer

Usually if a catalyst is clogged to the point the engine won't run, it won't all the sudden unclog itself. It would be a first for me to hear of a catalyst being clogged only when warmed up.

To verify a restricted exhaust the best way is to screw a back pressure gauge in the O2 sensor hole before the cat. When the engine is running the pressure shouldn't be anymore than 3 psi at 2000 rpm. It might have been a coincidence the engine ran with the O2 sensor out. Did he unplug the O2 sensor connector to see if the engine ran better with the O2 sensor screwed into the exhaust?

Crossed battery connections might of nailed your engine controller or any other solid state device in the electrical system. The problem really needs to be diagnosed again to see what is actually missing when the engine doesn't start after it has stalled.

Response From jtmill02


Usually if a catalyst is clogged to the point the engine won't run, it won't all the sudden unclog itself. It would be a first for me to hear of a catalyst being clogged only when warmed up.

To verify a restricted exhaust the best way is to screw a back pressure gauge in the O2 sensor hole before the cat. When the engine is running the pressure shouldn't be anymore than 3 psi at 2000 rpm. It might have been a coincidence the engine ran with the O2 sensor out. Did he unplug the O2 sensor connector to see if the engine ran better with the O2 sensor screwed into the exhaust?

Crossed battery connections might of nailed your engine controller or any other solid state device in the electrical system. The problem really needs to be diagnosed again to see what is actually missing when the engine doesn't start after it has stalled.


I'll make sure to ask about the back pressure when I talk with the exhaust guys tomorrow.

I don't think he disconnected the O2 sensor connector, he just unscrewed the sensor from it's hole. (I'm not sure I understand your question correctly, so please let me know if this doesn't make sense - I assume that you mean the hole would be plugged by the sensor but no information getting back to the computer because the cable was disconnected from the sensor.)

I didn't get a clear explanation of why he took the O2 sensor off - my understanding is that he already thought it was an exhaust restriction, so he took off the sensor to relieve the pressure and he says it ran normally once the sensor hole was open.

They seemed set on this catalytic converter solution and were reluctant to go after more electrical/timing/fuel mix problems because there were no error codes to indicate any problems. Is it possible that the lack of computer error codes could be a result of damage to the computer? If yes, how do figure that out?

Response From jtmill02

UPDATE - Car went to exhaust shop yesterday morning. They quickly ruled out the catalytic converter as the problem - all the exhaust testing was fine. Back to the dealer, where they apparently spent a good part of the day trying to figure out the problem. They finally decided the problem is a fried fuel pump control module. This makes more sense to me given the mechanism of damage, so I was satisfied with the explanation, even though I don't have any idea what a bad fuel pump control module would act like. The part will take a couple days to come in but will cost half of what replacing the cat would.

Thanks for everyone's input. I'll update when the part gets replaced.

Response From Hammer Time

My gut is agreeing with your gut. It's not acting like a plugged Cat and appears electrical but the only way you are going to find out is by doing some testing during that period when it won't start. You need to test for spark, injector pulse and fuel pressure to isolate the cause.

Response From jtmill02


My gut is agreeing with your gut. It's not acting like a plugged Cat and appears electrical but the only way you are going to find out is by doing some testing during that period when it won't start. You need to test for spark, injector pulse and fuel pressure to isolate the cause.



To clarify, I'm not sure that it wouldn't start again right after it died. The technician told me it would run again after sitting for a few minutes and that's what I did - I didn't attempt to start it earlier and it did start right away after sitting.

I did ask about the some of those issues, but they told me that there were no computer error codes so they didn't look further into it.