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I have spark, plugs were dry, so now I'm looking toward the fuel system. It will occasionally start, I noticed that when it does start I can hear the fuel pump and when it won’t start, I don’t hear the fuel pump just prior to turning the key fully forward. My repair manual instructs me to perform testing, first with the fuel pump relay. Problem is, It’s not on the firewall within the engine compartment as indicated in the manual, Where is it? Also tried applying 12V to the fuel pump test connector pin however, no sound from the pump. Will the pump always run when 12V is applied to the test connector or once max pressure is reached the pump will not run any longer? Looking at the schematic of the fuel pump wiring diagram it appears applying 12v to the grey wire will make the pump run, will it?

Thanks

The owner's manuel should say where. If Not! buy the dang relay at GM and look at their screen for where. I'd start with the relay and then it's possible that you need a fuel pump. Good luck- T

the rear window on my 2001 GMC Jimmy wont open,I push the button on the dash, it makes the "noise" like somthing is moving,but not the "click" it used to make,when it did open,My problem is, how do I access this lock/latch mechanism to repair it? I can crawl over the back seat and look at a rear panel of the rear fold down door,but, see no way of removing the panel to access the rear locks.The repair manual says nothing about this problem,and without the rear window hatch open, the tail gate does'nt open eitherso do you have an answer?

You may do some damage in the process because the hatch won't open but the inside panel has to be removed to access anything

Dear Group,

I currently own a 1988 GMC S15, 4 cylinder, 2.5 liter, 5 speed manual
transmission pickup truck. It was a great running vehicle till this year
it started to act up! Back in May and June I drove it to work, and then
in the morning when my shift was over (I work nights) it ran like a champ
then started to 'shut totally down' it struggled to run, then wanted to
shut down HARD. I restart it would burp, gurrgle, gasp chufff and shake
then die HARD. I restart again, and the entire truck shook and rattled, so
bad, my coffee and water jugs sloshed allover! I am told, it could be the
hydraulic clutch going out, the timing system going out, or the Electronic
Control Module. The Haynes repair manual says the E.C.M. could be in one
of three places.. Passenger side kick panel on right side under the dash,
behind the glove box, or inside the the instrument cluster.

How do I remove the speedometer cable from the instrument cluster?
(Would there be any replacement 1988 GMC S15 instrument cluster for
a 2.5 liter, manual transmission, with or without trip odometer?) I do
want to find out where the E.C.M. is, and what I can do to remove it,
since I am out of money till pay day (1st of December I get paid monthly)
and like to save some towing charges, and repair costs if I can. I wish I
can hook up a USB port to the computer, save the critical information to
a flash drive as a back up, remove the good component off of the unit
and get a new E.C.M. and reinstall the part. :) Or a simple Reboot would
help fix my E.C.M. But, what is the common spot to find the ECM and any
tricks to get it removed without breaking the wire or connectors.

Any thoughts on this? Please help? What brand of E.C.M. has a good
warranty on it, lifetime warranty and reliable.

You really think you have it all figured out huh? I'm afraid your theories are a bit off the mark. Even if your wild guess of a bad PCM beats the 200:1 odds that your right, your theory of using a laptop to program it is possible if you go out and spend the $20,000 in equipment needed to do that. The flash drive isn't going to cut it.

If you want to diagnose this properly, use this link

NO START DIAGNOSTICS

Dear Hammer Time,

After replacing the injector, key ignition, fuel pump, fuel sending unit,
flushing the tank, purging the fuel lines, replacing the fuel filter, and fuel,
with excessive down time due to budget cuts and I only get a check once
a month, so this is a luxury to get going after bills are paid, I realize the
OBD-I computer may have been damaged after an accident in 2008 on a back
road in Central Texas. After that accident, 2 or 3 shade tree mechanics did
service this truck to rebuild the rear end, and later the transmission.

I've been taken for a bad ride in the service end of the deal. Now with that
said, I simply want to know the location or common location of the E.C.M or the
O.B.D. 1, computer on a 1988 GMC S-15, 5 speed, 2.5 liter, pickup truck. Is it
behind door number 1: Instrument Cluster, 2:Glove Box, or 3:Passenger Kick
Panel under the Dash where you rest your foot / leg?

(Also, is there available New Old Style Instrument Clusters for a 1988 GMC
S-15 with manual transmission, and a trip odometer available? Some salvage
yards may not have them, and wonder if it's another Obsolete Discontinued part?)

Thank you for responding, I just hope I can find a service professional to work
with me, and check the OBD-1 computer. If not, I'll wait till Jan or Feb when I
have the financial means to do so. THANK YOU! Happy Holidays, Happy Chanukah!

Sincerely,
irishmantx
76531

P.S.

Well I stand corrected about diagnosing and being a bit high tech on the
matter. Since the "Car MD" infomercials are coming out, I felt it would be
'nice' to have all cars with a USB plug, load some diagnostic software on a
laptop or desktop, 'troubleshoot' via the computer to computer interface,
and get an accurate electronic interpretation of the trouble codes on the
car in question, and apply corrective measures to resolve the issue at hand.

I would have thought that after throwing all those parts at it and having no success that you would be ready to change your methods, but apparently not..........LOL
The ECM is right under the dash on the passenger side.


Well I stand corrected about diagnosing and being a bit high tech on the
matter. Since the "Car MD" infomercials are coming out, I felt it would be
'nice' to have all cars with a USB plug, load some diagnostic software on a
laptop or desktop, 'troubleshoot' via the computer to computer interface,
and get an accurate electronic interpretation of the trouble codes on the
car in question, and apply corrective measures to resolve the issue at hand.

No, your not too high tech at all. If fact the junk your seeing on the infomercial is really low tech. They are nothing but OBD2 generic readers that can be loaded on to a laptop. They are the DIY version of the real tools but with only about 10% of the capabilities. Programming is possible from a laptop and many scan tools now but the cost of this capability would be well over $10,000 It's a whole lot more advanced, and proprietary for that matter too, than a simple flash drive.

Just the speedo cable for this:

If like the older (1984) S-10 Blazer I owned I got to it best thru the speaker instead of from underside. If this year still has a dash speaker it will come right out and you can lube or replace cable that way. Can't speak for every model year of everything but did that one just that one as it was annoyingly noisy and I just wanted to lube it and that's all that one needed,

T

Good luck buddy. Kitty as I call her is the site's mascot critter. She's a 2002 model mostly Balamese and the most gentle thing I've ever known. House has enough cat hair to stuff a decent mattress but she stays.

I'm just nuts enough to be a now retired ASE certified mechanic and use a cat for an avatar

I didn't know they made Grandas that late. I've owned more cars than anyone I know short of a car dealer and one was a 1975 with the 302 V8 which was actually pretty lame for power but didn't give me a hard time. The door were so damn long which is great for people to get into the back but if parking was tight somewhere there wasn't room to open them.

Regulars are here to help as best we can.

Take care,

Tom

Dear Tom,

Thank you for the helpful advice. I'm waiting till pay day to get the Engine Control Module ordered and
replaced. Also, things acted up after the accident in 2008. I hope I didn't damage the electrical leads or
connectors. I have to replace bulbs all over the truck periodically, possible short to ground, or some wire
exposed. I found a bulb totally blown inside the shell. I hope replacing the E.C.M. solves the problem long
enough to get me back to the mechanic to check the wiring and or total replacement of the T.B.I. ? If the
connectors not letting the injector work?

Well, I hope to be able to help other souls who have similar problems and bring quick solutions to keep
their S15's and S10's on the road. :) I got to find a good mechanic that don't use spit and bailing wire. lol

Shalom and Happy Thanksgiving,

Michael D. Lucas
76531

Dear Tom and Group,

It turns out, after having one to many shade tree idiots, think my truck is a carbureated
system, after I tell them its fuel injected, the 'tune up' damaged the Hall Effect Switch -
O'Reilly Part Number ME62 $94.99 + tax The distributor cap was not properly seated, and
the rotor 'damaged' or 'chewed up' this part.

A 'better' technician did test with the noid light, the Hall Effect Switch inside the distributor
system was damaged, and not letting current / electrical flow to start the injector. In short
it mechanicaly cranks, but electronically dead. :P I've ordered a new distributor with a lifetime
warranty. I hope this solve the issue for sure, if not I'll try to keep everyone posted if they are
interested...

Main thing for sure, the 1988 GMC S15 Distributor has lots of integrated teeny tiny parts inside
the distributor that can be damaged and also cause issues with starting (That is, when the distributor
cap, is not properly seated and snapped in, thus the rotor acts like a garbage disposal,
chopping up anything inside!) . Most of the micro parts are inside this particular distributor. For you Chevy
lovers who know what I'm talking about. I want to know how many components are inside this particular
distributor?

If possible please let me know?

Shalom,
Michael D. Lucas
76531

Parts for these now old cars still can be found. Start Googling away. Here in Eastern MA land is so expensive they can't afford to keep cars in the salvage yards unless particularly valuable or collectible and rust is king here so those and the vintage are mostly worth more to crush for the metal than wait to sell parts.

Ask a local salvage yard and they may know where to look for things like lenses and the headlamp bezels. Bet whole good engines can still be found if you really think it's beyond reasonable repair.

I use that line "Measure twice cut once" type of phrase a lot. Try do diagnose stuff to the fullest and not waste bucks but target what you really need.

Restored a 69 Lincoln in 1993 and was easy to find parts for that - brand new old stock. Place in CT had everything and warehoused lots of stuff in Kansas I think. It was pretty wild seeing the old packages of new dinky parts with the words FoMoCo on them! The Lincoln parts cost some bucks. Bet for Granada it's much more reasonable. Seek and ye shall find.

A member here named Nacho from Hermosillo, Senora, MX might even have info for parts which could be shipped from AZ as he owns an A/C shop there but buys tons of stuff in AZ and sends someone to go get it.

If that works for you he's a great guy and would help. No language barrier with him either. You can find him at ..........
http://acsource.net/acforum/index.php?sid=7acf1fcd552e644d7d8eeeb77edc058a which is an A/C site but just send a private message.

One of ours is into old cars too user name " chickenhouse " . To send private messages here you click on the user name and see the option to send one if they have enabled that.

Good luck with the hunt. Guessing these cars are NOT all rusted and they are fairly easy to fix as things go.

Go for it,

T