Can you guys help me figure out a car problem?

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i .. OVER THE YEARS I HAVE HAD MANY GM'S WITH BAD IDLE SPEED MOTORS , VERY COMMON , THEY WOULD GET TO SLOW TO CATCH IT FROM STALLING , ALSO HAD A BUNCH WITH BAD COMPUTERS , THEIR SYMPTOM WAS , WHEN ALMOST STOPPED OR AT A COMPLETE STOP , THE ENGINE WOULD SHUT OFF LIKE YOU TURNED OFF THE KEY , BUT START RIGHT UP & BE GOOD FOR ANOTHER HOUR & THEN DO IT AGAIN !
 
Since you have a mid-90s GM car, it's pretty likely there's a plate somewhere under the hood that holds the 4 or 6 coil packs. Rather than a dedicated ground, the coils simply ground through their mounting to the plate, then to the body.

Over time the interface between the coil and plate corrodes and creates a weak/bad ground. I've known three GM cars that had weird electrical issues(one refused to start entirely) that this was the cause of. Remove all the coils, sandpaper the crap away, put it back together.

This is true. On almost all early GM 3.8 engines, the "plate" under the coils, which is actually the iginition module, tends to corrode and cause all types of problems. Clintard, if you remove it, make sure its clean and none of the gel inside of it is melted. Usually when these go bad you will get a rough running engine, but I don't think it would be an intermittent problem. Does it have the "service engine soon" light on? If it does, you can take the car to any Autozone and have the codes read for free. The 3.8 engines were also notorious for the camshaft magnet coming off, which will make the engine run like crap.
 
Im sorry i took so long to get back on here and update this!!

Yes i have a check engine light on.

Earlier this year, the fuel pump went out. It was a real bear getting the gas tank down let me tell ya! Sheesh. You have to take an exhaust pipe down to get the tank out. Strap bolts were rusty just spun. I got sick of messing with it so i torched them bastards out. I know, not smart when right next to a fuel tank! LOL. I didnt burn myself to death tho and i got the tank out. Put a new fuel pump in it, rigged some strap bolts and put the tank back up. Car started and ran so i was proud of myself. My girlfriend went to get it and drive it home, and im not shitting you, she drove it 5 feet and one of the O-rings on the plastic fuel hoses blew out and start pissing gas everywhere so it stalled. DAMN IT. I found a similar O ring and tried to make it work, but it would only last a few miles and they would blow out again. I figured the plastic fuel line was warped or something. Bought 2 new fuel hoses and put them on. Drove the car 10 feet this time and it stalled again! I could hear the fuel pump running but NO fuel pressure.

Had to take the damn gas tank down AGAIN, and when i took the sending unit off the get to the pump, i snapped the damn hard line on the sending unit! The gasket between sending unit and fuel pump had blown out.

Got a new sending unit and its a different design so i had to figure out how to rewire some shit to make it work. Put the pump on it and noticed it just didnt seem right. It had a little play between the sending unit and the fuel pump where they meet. Theres a gasket between them. It seemed like enough pressure to keep that gasket sealed so i put it all back together, put the gas tank back up and strapped it in. Drove the car for about 20 miles and it stalls AGAIN. That bastard gasket between sending unit and fuel pump had blown out again.

This time im absolutely FURIOUS. I took the tank down again, took out the sending unit and fuel pump and brought it up to the parts store. Not autozone but a reputable parts store in our small town who sell OEM stuff. They gave me the wrong damn fuel pump from the beginning! I guess they gave me the pump for an SSEI supercharged bonneville and it is just SLIGHTLY different so that explains why it didnt feel as snug against the sending unit as it should be.

So, i get the right fuel pump, put it all back together, put the tank back up and she had perfect fuel pressure. Car has ran perfect ever since that whole bitch of an ordeal!

These things have a sealed fuel system. If you forget to screw your gas cap back on, youll get a check engine light. The check engine light has been on in this thing since i bought it, but the only code it showed was the one for the gas cap being off. There are tiny pin holes in the top of the tank itself so its not perfectly sealed and unless i replace the gas tank the light will stay on. I can live with that. My grandpa is a retired GM mechanic and told me stories about how they would pressure test the fuel systems with nitrogen or some kind of gas that would show up under UV light to find them pinholes and seal them. Screw all that ill just live with check engine light stuck on.



UPDATE on the stalling issue. Im 90% sure it is fixed now.

I went back to the parts store and had them bench test the alternator i turned in for core, and it was indeed bad. So i didnt waste my money on alternator and battery etc.

I spent a day chasing wires and checking for bad grounds. I ran a big fat ground wire from battery to a mounting bolt for the alternator and it didnt help. It would still stall.


After alternator and battery and fixing the cables up it stays rock solid 12 volts off, 14 volts on now even at idle. When it stalls the volt gauge stopped dropping before it stalled but the sumbitch is STILL STALLING.

I cleaned the grounds under the coil packs and they werent very bad. Still stalling at idle etc.

I thought the serpentine belt was slipping, so i changed that. That resolved the ticking noise i was talking about but the car would still stall.

After a bunch of reading next i decided to check and see if the IAC, intake air control valve was dirty and clean it. I took it out and cleaned it. It was filthy. This actually made the thing stall worse.

Somehow in the process of taking the IAC off and cleaning it, i broke a vaccum hose down by the vaccum modulator for the transmission and didnt realize i had done it, so the thing wont shift until 4000 rpm's and is reving up to 3500 when started. I thought i fried the computer or something.

Changed all the vacuum lines and fixed the shifting/revving when started. But still stalling.

I took the IAC out again and with the IAC in my hand, i was gonna test and see if it was working. Told her to cycle the key on, then start it. She cycled it on, then back off, and the damn plunger in the IAC jumped out and i lost the spring.

Paid 50$ for a new IAC valve, put it in, thinking this HAS to be the problem. Started it up and ran it down the street and it starts dying again, worse than ever before. I just kept driving it all over town, letting it idle, hitting stops signs etc and it finally cut the shit out.

I think when installing a new IAC the computer needs some time to learn and adjust things for it to work. Tonight i drove the car for about an hour, in town, stop and go, hitting every stop sign and turn i could and i couldnt get it to stall out. The idle drops down and gets rough like its going to die out but so far it hasnt died.

SO, i guess the motor in the IAC valve got lazy on me.


I hope and pray this stupid car is done haunting me for a while. Next is front wheel bearings. Id like to keep this as a beater to drive during the winter to keep salt off my other car, but if it keeps its shit up im going to sell it.
 
If it starts acting up again, im done chasing problems. I think i will just figure out a way to adjust the idle speed up a tad if i can. If its some computer controlled bullshit i will adjust the throttle cable somehow i guess.

My whole family are GM fanatics. My grandpa's a retired GM mechanic who wrenched for 45 years. I may get disowned by fuck GM. Im trying toyota next.
 
I've had a few cars that needed some fixing. And all of them had different problems. Yet I was able to fix all of them with the same tool. works every time.

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