How can you check your timing???

[GRANDFURY]

Like the tilte says just wondering how to check the timing on my car. It's a '89 GP with a 2.8.

[Anonymous]

How could your timing go bad?

[GRANDFURY]

I don't know the damn thing has been running like crap for awhile now. It's mainly at idle it runs real rough and sometimes stalls and then other times after it has warmed up and been shut off it wont restart for 30 mins to a hour then runs fine again. I have put in a new crank sensor, new wires, plugs, air filter, the cat doesn't make any noise, pcv valve is new, no vaccuum leaks, battery is brand new (two days old) , O2 senor, all plug wires have spark, altenator tested fine, idle relearn. Now i'm kinda outta ideas, sometimes I can get it going after it stalls but it runs like it is only off a few cyilnders or something and has no power and when the gas is let off it dies right away. The problem is intermittent and happens at all temps, gas levels, and times of day or night, wet or dry. The only other thing I can tell you is that sometimes the exaust smells like gas a bit and at idle with the brakes on and right before it stalls the voltige meter is very very low (almost in the red). So I was thinking maybe my timing is off but then it would happen more offten right??? Sorry this is so long

[wiccanferret]

Long is good. Details are good. IAC sounds like it could be it. Also sounds like your ECM might be corrupted, but that seems to happen very rarely in GM's. You have changed the fuel filter too, right?

[GRANDFURY]

yes fuel filter has been done and I have cleaned the IAC but it was pretty filthy, maybe i'll try one of those couldn't hurt right. Also my speedo is off by 15 kph. I don't know if that is related but there it is. Thanx for the tips guys. I appreciate it.

[wiccanferret]

That would be a problem with your wheel speed sensor, if an 89 would have WSS and not a cable. But if you DO have a WSS I guess it could have something to do with some of the other problems, except idle.

[Anonymous]

SES light on?? Maybe its your MAP (my 88 had a bad MAF, but the 89's don't have them).

[3100 MPFI]

sounds liek a bad ECM. If your speed is off, but you have not changed anything with the transmission, or the ECM, then sounds like your ECM, or the MEM-CAL is taking a crap. I would try getting a new ECM and and chip, and see if that fixes the problem.

[RLJ]

Shorted fuel injector. I'm almost willing to bet on it. I've been down this road 3 times with my car. Most of the other suggestions would set the SES light on. . Should be 12 ohms. Any lower and they draw too much current from the ECM which can cause a stumble. REAL low and the car will die completely. Let it cool off and it will run for a while.
A way to check without pulling the plenum is to disconnect the ECM. Find the injector wires (usually pink & blue) and measure there. They are wired in parallell banks of three. With all 3 connected, you should read around 4 ohms on each bank. any lower, and you're pulling the plenum to read them individually.
Hope this helps!

[geoffinbc]

Also check the engine coolant temp sensor

[evilmiata]

Also check the engine coolant temp sensor

...and the coolant. Make sure its not muddy. Does it sound like its boiling when the engine is shut off?

[GRANDFURY]

Acctually right before this problem started the fan stoped turning on and it would over heat and then about a few weeks l8r it started this stalling buissness.

[GRANDFURY]

There has never been a SES light or any light. Just the voltage drops and the oil pressure seems to get low too right before it happens and it is always when hot never cold. Cold it fires right up. Please don't say injectors

[GRANDFURY]

Where is the coolant temp senor? And I have done nothing to the tranny or the ECM. How would I go about ordering a new mecal? Are they expensive?

[Anonymous]

The memcal is a chip on the ECM board.

http://www.w-body.com/inside-stuff/memcal.html

http://www.w-body.com/inside-stuff/ecm-pcm.html

From what I understand you need a new ECM (the whole computer board). Should be able to use any ECM from 88-93(? before the 3100?) and put your exsisting Memcal prom chip on the new ECM. Someone correct me if I'm wrong.