kirkcomer

A friends 1988 GTA. 67,000 miles. New IAC, TPS, south bay injectors, plugs, wires, maf, maf relays, fuel regulator, upper intake gaskets, fuel filter, air filter, distributor and I'm probably missing some other new things. I also have a spare ecm that worked fine in my car. It will run perfect one time (IAC 34 at idle) and you stop and restart the car then it runs like total crap... IAC maxed to 160 at idle, rough, etc. Also does weird things like not wanting to start (turn key and nothing... engine does not try to start) and the headlights today dodnt want to come up... but then i turned the car off and then the headlights work fine. Climate control and radio both have constsnt issues. Could it be wiring harness related? Im starting to just throw parts at it and i hate doing that. Any suggestions are appreciated.

zed-028

unfortunately this sounds like a test light, voltmeter and a wiring diagram scenario.

kirkcomer

That's what I'm thinking too. It was getting code 36 and 34 for a while and my brother and I went through all the troubleshooting steps. Found a black ground wire that was questionable. Replaced that wire but everything really looked okay. Took off the aftermarket MAF and put the MAF off my car on it and the codes went away(for now) but who knows.

I set the timing, IAC and minimum air adjustment per the instructions on this site. Its frustrating. Two mechanics worked on it before me... looks like its heading to a 4th person if I can't figure it out soon.

After working on this car... it honestly makes me want to sell mine and mine runs great. lol

kirkcomer

Not sure if it matters but car always runs great at wide open throttle.

M G Brewer

I'm right there with you man! I was working on mine hard to get it running so I can drive the fire out of it, but it keeps flashing code 36.

The only way I can get it to run right is to:

-fire it up (runs excellent until it is done warming up)

-then once it starts idling extremely low, I adjusted the idle screw up about a 1/4 turn every few seconds (approx. 10-14 quarter turns), then out of nowhere it revs high and holds there.

-then I adjust the idle back down until it sounds like it should to me (tach is reading wrong), and it runs perfect! You can drive it all day long, until you shut it off.

-turn it off and back on and the same problem comes back.

Now I know all the haters are gonna be like, "Your stupid!", "Your doing it wrong!", blah, blah, blah.

Tell me how I could get it to run great doing what I did and why it reverts back to its old ways as soon as I shut it off and fire it back up!

kirkcomer

I feel your pain. Haha
​​I ran it 2 hours today and drove all over the place... ran perfect. Turned it off for 5 minutes and it ran like crap. I just cant figure it out. Ill check fuel pressure for the 3rd time tomorrow. 43.5 psi with fuel reg vacuum plugged and intake port capped. Im getting to know all these different check and setting instructions too good. Lol

Tootie Pang

iTrader: (2)

Have you checked the EGR valve?

Also, a great way to check for any vacuum leaks is to get a can of starting fluid spray, and with the engine idling well and then poorly, spray bursts of it around all the vacuum stuff, hoses, devices, manifold seals etc. If your engine revs up, you've found something. The idea is if there is a vacuum leak, the starting gas will get sucked in and your revs will climb.

OrangeBird

iTrader: (1)

Ive always had success when using this method to use a can of carb cleaner instead of starting fluid . I would think if you got a bit too spray happy with the ether you could have a nasty little fireball on your hands if something hot goes and ignites it . The carb cleaner will still produce an RPM change in the instance of troubleshooting a vacuum leak but is far less likely to ignite than the starting fluid is ...

hockeyman48

My guess is bad ground and/or positive cables and possibly fuse link wires. With age of cables ,I would change all of them.You cant see internal corrosion in wires/cables. Check engine ground strap at passenger rear of engine also. Reasoning is multiple electrical intermittent problems. Sounds ground related to me.Cost is probably under 50.00 Because of corrosive location of fuse link wires at starter positive cable, I moved mine up to battery positive post by splicing in wire extensions. Good Luck

kirkcomer

Thanks for the replies. Car is officially running great! It turned out not one but two different brand new aftermarket MAF's did not want to work correctly on this car. One was a Walker and the other was a Duralast. Finally bought remanufactured MAF from Autozone and car runs perfect.

Still have climate control and radio issues but the car itself has been running great for a couple weeks now.

M G Brewer

My idle issues got fixed by replacing the ECM/chip.