Ok, Ive spent about the last 2 hours searching and really havent found anything like the problem im having. Ill start off with the problem, when I start my car up, it starts right up but then stalls right out, if I rev the engine it will stay running but once it drops below 1000 RPMs it stalls out again, if I tap the gas it stalls out also. After a few starts and revving it will drop below 1000 RPMs and start to idle very rough for a few seconds, then go up to around 1100 and idle up to 1700 or so and idle back down, it does this for roughly 5 minutes and then everything is fine. It drives fine, stronger than ever, im fresh out of ideas. I am going to put it on the scanner tomorrow to see if I can find anything at all wrong, help if you can!! Please!!

Heres a list of what all ive replaced when it started having problems, different from the current one.
Temp sensor, O2 sensor, Plugs/wires, dist cap/rotor button, fuel filter, O rings on the injectors(visual inspection on them also), Knock sensor(was unplugged and the old one cracked at the tip), ESC module, FPR diaphram, intake manifold gaskets(had a torn one), TPS(adjusted to .56), cleaned the IAC and TB, MAF sensor and both relays, checked all vacuum lines, and along the intake system. Thats all I can think of right off.

 

did you check all the injectors to see if they were leaking? You should get a mechanical fuel gauge to see what your fuel pressure is while it's acting up, and when it's working like a charm.

Might as well change your fuel filter since you're in the mood for some general maintenance, right?

 

Already changed the fuel filter, dunno how to check the injectors for leakage? Theres no fuel or smell around em the best I can tell, after I put it on the scanner tomorrow im gonna get a fuel pressure check guage and check the pump at both times. Thanks.

 

Update: Checked fuel pressure, everything checks fine there. Put it on the scanner today and most everything seemed normal. The 02V was .45 and in open loop it would switch from lean to rich, I was told it shouldnt be doing this, the spark advance was 20 degrees, the RPMs on the scanner read 1100 when the tach read 1500(dont know if this matters much). It was idling fine then jumped up to 1500 and idled, the TPS was realy quite funky acting, it was at .27 when we first hooked the scanner to it, and when revved to 4k it would only jump to .78. We turned the car off but left it in the run position and then the TPS wouldnt move at all from .27, we shut the car off and turned it on again and then it would go from .27 to 4.33 at WOT. Ive replaced the TPS twice so far, so im just lost pretty much. Will a bad TPS(maybe, but 2 so far?) make it run rich and not start when its cold? Or should I look to the ECM? Please help, im just complete confuzzled! Thanks.

 

to test the injectors for leakge just take them out and let them hang there and watch for drips. If your fuel pressure stays constant with the car off (within a matter of hours that is) then you shouldnt have a problem with the injectors.

I am no expert on TPS by any means, but I can imagine that those readings are not exactly what they should be, at all. I think you should look at grounds, maybe corroded/corroding vacuum lines.

I doubt it is your fuel pump, and I dont think it's your ECM either. More tests will help

What was your fuel pressure when it started to "act funny" ?

What all changed when it started "acting funny". This will give us a much better idea of what's going on with the car

 

Even though you have replaced the stuff, unplug your MAF and see if it doesn't stall.

 

Ok, ill check some more things in the morning, like unplugging the MAF and im going to dig around the wires along the TPS line. About the only thing I could tell right off when the TPS started acting up, via the scanner, was that the RPMs shot up to around 1500 and stayed there, almost like I had my foot on the gas, then it would idle real low and shakey, really about it, other than it starting and stalling out, Ill be able to really get in there and check some stuff in the morning and ill post what I find, thanks for the help guys, this is really giving me some areas to look at!

 

Ok, first thing I did was pull the MAF plug, the car started right up and idled great, what does this mean!!! im soooooo confused now lol, awesome though, thanks a ton for the idea Red Devil. Now what to do though?

 

Troubleshoot the MAF circuit. You have either a bad realy or two, or a bad MAF or possibly a bad connection. Sorry.

Also, the force of programming may have hidden any other problems as well, so it may not be your only problem.

 

bah, ok hehe, ive replaced both relays and the MAF sensor, ill put in another relay that I know is good and go from there then. Thanks for the info!

 

Make sure all your relays are plugged in properly to the right relay. On an 89 you should have 2 square relays and the fuel pump relay is different. Did you get a remanufactured MAF, sometimes they are bad.

 

Courtesy of my buddy in the pop can helmet:



This is on an '86 t/a IIRC. Looks the same on my '89 GTA but all three of my relays are rounded. HTH.

 

Aye, Trickster sent me a pic of where they were on my car, the are the same local but side by side closest to the fender and both are rounded. I was told that both relays are the same, because I asked someone because they had 2 different numbers on top of the relay, 8309 and 5311, which ive replaced both with new ones, not saying that means they are good though. The MAF sensor I bought was a brand new one from advanced auto, I still have the old one, I have a troubleshooting diagram for it somewhere I think. Only thing that sucks, I cant troubleshoot it right now because its not doing it lol. I had to run get a tool for my other car, so it was warm and the problem doesnt happen when its warm, only when the engine is cold. But as soon as its cooled off enough and not starting ill be able to troubleshoot it better. Thanks for the help guys, I feel like im actually making progress now.

 

well I swapped out both relays with known good ones and swapped out the MAF sensors, and still no change. I wiggled the wire going into the MAF, but hard to tell if it made any difference, it was idling up and down and I moved the wire and the idle evened out, but It could have been the car evening out on its own like it does sometimes. About the only thing I can think of doing otherwise is a continuity check on the wires themselves, other than that im pretty lost.

 

One thing at a time. The MAF may have been the stalling problem. The searching idle is something else. Get rid of the stall then we can look to IAC and TPS cleaning/setting.

 

Aye, thats my main concern is the stalling problem, but nothing has fixed that yet, I was just stating that I replaced the relays and MAF, but one at a time and checking to see if the car was still stalling out. So far its not the relays and Im not real sure about the MAF, I know its possible to get a bad one. Im going to check the wires tomorrow and see what it looks like from there. You guys are really helpin me out, thanks for the info and ideas!

 

well, I did a continuity check on the wires going from the connector plug to the relays and checked the grounds, everything checked out fine. Could the fuel pump relay have anything to do with this? I only ask because the orange wires coming from the burn off relay connect into the fuel pump relay and my fuel pump relay looks VERY nasty, lots of grease on it and some bare wires showing on the back of the plug. Other than that Im pretty lost, im going to see if my friends new RS has a MAF sensor setup and see if I can swap his sensor and relays with mine to see if it works.

 

Small update here, im completly lost! hehe, ive checked every wire I could find in the haynes schematic going from the MAF to anywhere, and put a continuity check on any that I could reach with my DMM leads. I think I really need some help/expertise to continue tracking down this problem, any ideas/suggestions? Thanks again.

 

Well, I hopped on over to the Electronic boards, thinking "wiring problems" and a guy over there recommended I replaced the IAC. Took his advice and my car is now fixed and running perfectly! Just in case any wanted to know what ended up being wrong with it. Thanks for all the help guys tracking down this problem!