Trouble with my '92 Silverado

[55Hardtop]

Hey guys. I really need some help.

I've got a '92 Silverado, C1500 2WD, 350 TBI motor.

The truck's been idling funny lately, I figured the IAC valve was going. Well, yesterday the truck died on me in a parking lot. It'll start, but runs on every other cylinder. Also while running, the check engine light flashes. I've had a hunch the computer's been going bad in the truck. Here's why:

I got a check engine light for a bad ignition module. I replaced the module with a new one, and swapped in a good ESC module also just to be sure. Cleared the codes. Same day I get the same check engine light. The only other code the computer spit out was a EGR sensor error. Because it kept giving me the same trouble code for the ignition module, I started thinking maybe the ECM was going bad. The truck has a few hundred miles short of 200k on it.

I've gone through my mental checklist of anything that could cause the truck to run on every other cylinder, and the only part left that I'm not sure about is the ECM.

Can anyone out there give me some advice on this? Could the EGR be causing this problem? I don't really have the money to just throw parts at the truck, and having to leave it sitting in a parking lot yesterday sucked, I hate leaving my girl in strange places like that!

Thanks guys, appreciate any advice you can give me!

[min301]

Re: Trouble with my '92 Silverado

Could be a couple of things.

The distibutor may be bad in two ways, 1) the pickup, or the shaft could be the issue, or 2)
the wiring leading from the coil to the distrubtor and/or the wiring from the distributor itself may be faulty.
We see quite a few.

Could be a PCM related issue also, but first I'd check the wiring at the coil, to the distributor.
Try starting the engine, then wiggling the wires at the connectors.

Keep us updated...

[SpiderGearsMan]

Re: Trouble with my '92 Silverado

the tbi housing gets clogged up with soot , the procedure I used was , remove throttle body injectors and fuel regulator from throttle body
soak in carb dip
replace fuel pressure regulator
ALSO :check the coil tower , if it is all crusty , replace the coil , that causes all kinds of driveability problems on the H,K and M motors , replaced hundreds
other than that , basic compression test , leak down
we have also been getting sticky valves , valves hanging open on the highway
cheap gas is really causing problems

[70.5CAMARO]

Re: Trouble with my '92 Silverado

the olny prob i ever had on my 91 was teh pcv port getting clogged solid and it blowing oil out of the dipstick while i was on the highway. lol that was a tough one to diag, only burn oil while it was goin over 60 mph. and it ended up not burning it, just thought so causeit was blowing right on the exhaust.

[TC]

Re: Trouble with my '92 Silverado

cheap gas is really causing problems

It's that an oxymoron.

[70.5CAMARO]

Re: Trouble with my '92 Silverado

cheap gas is really causing problems

It's that an oxymoron.

why is that an oxymoron? cheap gas breaks down much faster that older gas did, It also burns diferant that older gas did. Cheap gas tarnishes injectors in a matter of months rather than years. gas wil go bad in my garage in 2 months in a can when it used to go take a year

[squirrel]

Re: Trouble with my '92 Silverado

cheap as in price, not quality....is what TC meant....

[JOES66FURY]

Re: Trouble with my '92 Silverado

My 91 went thru 3 computers new off the shelf before I got a good one...sounds like you were having similar issues...I was going into the smame type of "loop" you are, the techs at chevy told me it was everything but the computer, 02's,IAT,Idle controll, and I forget what else...every sensor on that thing was changed and after I replaced everything it still ran like crap, changed the distributor, cap/plugs...took it back and they said it wasnt throwing code so it was the computer....3 computers later...I got a good one...rumor was there was a bad batch of them from GM

[55Hardtop]

Re: Trouble with my '92 Silverado

Well, I got a new/remaned computer from Autozone yesterday, plugged it in, and the truck fired right up. There's still a little idle flutter I think is EGR related, otherwise it's running as good as ever, and defintiely feels like it's back up to power. Before it had a stumble off idle and generally felt down on power.

At almost 200k on the original motor, I'm gonna do a rebuild on it soon. But I just wanted a good daily driver motor, so I'm gonna keep the compression between 9.0 and 9.5:1, probably reuse the hydraulic roller I installed about 50k miles ago, swap in some decent aluminum heads, if it makes 300-350 HP I'll be happy. I want more torque than anything (considering a stroker crank), good vacuum, and being able to run 87-octane with no problems.

[TC]

Re: Trouble with my '92 Silverado

cheap as in price, not quality....is what TC meant....

Yap Jim understands me. ;)

[TC]

Re: Trouble with my '92 Silverado

here's still a little idle flutter I think is EGR related

That just might be like that until the computer settles in.

On my '99 Camaro, there is actually a idle set procedure that you do after disconnecting the battery or in your case changing out the computer. But basically what it says is to run the car for 5 minutes at idle in drive with the emergency brake applied, then your suppose to put the car in park and let it idle in neutral for 5 minutes. I know sounds kind of fishy, but it's right here in my factory service manual.

[SpiderGearsMan]

Re: Trouble with my '92 Silverado

called idle learn
why autozone ? I would have gotten a GM reman PCM at a dealer

[min301]

Re: Trouble with my '92 Silverado

called idle learn
why autozone ? I would have gotten a GM reman PCM at a dealer

Ditto.

[70.5CAMARO]

Re: Trouble with my '92 Silverado

called idle learn
why autozone ? I would have gotten a GM reman PCM at a dealer

problem being the price expenencially higher at the dealer than autozone. like 800 compared to a 150 or so.

[JOES66FURY]

Re: Trouble with my '92 Silverado

Well, I got a new/remaned computer from Autozone yesterday, plugged it in, and the truck fired right up. There's still a little idle flutter I think is EGR related, otherwise it's running as good as ever, and defintiely feels like it's back up to power. Before it had a stumble off idle and generally felt down on power.

At almost 200k on the original motor, I'm gonna do a rebuild on it soon. But I just wanted a good daily driver motor, so I'm gonna keep the compression between 9.0 and 9.5:1, probably reuse the hydraulic roller I installed about 50k miles ago, swap in some decent aluminum heads, if it makes 300-350 HP I'll be happy. I want more torque than anything (considering a stroker crank), good vacuum, and being able to run 87-octane with no problems.

Good to hear, I forgot I replaced all the EGR crap too....I hade about 180K on mine when the motor locked up...Lost oil to all but #7 and #8...smelled awful when I tore it down....it had 3 weak cylinders anyway so no big loss..replaced it with a new one from NAPA for 1200 bucks....50K mile warrenty...ranlike a champ til the trans took a dump