3100 wanting to die at idle. Mystery

[blackbombshell95]

At first it was a slight hesistation upon initial acceleration. First thought was TPS. Tested that, fine. Still i replaced it. Same problem. Then i thought it was my tranny. I had black Tranny fluid. Flushed it. Same problem.

The car is vibrating a bit at idle. Sometimes it wants to die. Not all the time. Every now and then at idle. It actually runs about 650 to 700 rpms sometimes vs teh usual 800 rpms. I had my alt tested 5k miles ago and that was fine. Brand new 96 mo. battery.

I do have the ffp pulley, but i doubt there is a problem there

I tested my fuel pressure at idle, and i showed 38 psi and 48 with vacuum.

I have Iridium plugs with about 12k miles on them <--- Haven't checked those yet.

[98mali]

Try putting a decent fuel injecter cleaner in the gas tank. If that doesn't produce results you may want to have a shop flush the injecters for you.

[imported_germ]

check for vacume leaks

[Doubt_Incarnate]

sounds like a dead cyclinder if you say it vibrates, if one or more cylinders arent firing or producing power otherwise it will feel lumpy. time to check the plugs and see whats going on in there

[blackbombshell95]

Already have used REDLINE fuel injector cleaner. usually u put a little bit at a time for regular maintaince. i put the whole bottle. lol.

I don't think there is a vacuum leak. wouldn't the rpms RISE and not fall??

[Doubt_Incarnate]

they use vacuum for everything, depends on where the leak is, if its near the map sensor, then it might do something funny. is it throwing any codes?

[blackbombshell95]

no codes. still haven't checked the plugs. i won't be able to do that till this weekend.

[blackbombshell95]

UPDATE: yesterday, i started the car, it was running a little rough as usual. After 20 minutes it sounded TERRIBLE at idle. it was vibrating like hell. omg i couldn't believe it. it wanted to die and die like it had an aggressive cam... THEN the check engine light came on.

I still ran it to work for about another 20 mins... I started the car a few hours later and its still running rough but no check engine light.

My question is If i hook up a scanner willl it show that code that displayed yesterday? or do i have to wait until the check engine light comes on again to source the problem?

[Doubt_Incarnate]

codes are normaly stored, so yes a scanner should pick it up.

[blackbombshell95]

Is there a chance that the code won't store? its a 95 non obd II.

[Doubt_Incarnate]

oh, so its one of those. isnt that like the feared obd 1.5? i'm not so sure on that one.

[Robb235]

I'm able to scan my '95 "OBD 1.5" just fine with my scanner. Go to Autozone and they should be able to take care of it.

[blackbombshell95]

i think its the 1.5. so i guess its still up in the air weather i'm able to pull a previous code

[Doubt_Incarnate]

it cant hurt to try

[blackbombshell95]

Well, the codes do store in obd 1.5... i have a code on egr 2 and egr 3 i think. And a crankshaft idle sensor i think...

Also, i replaced the TPS, and there are two different codes for the tps. some high and low errors. But the voltage is right in spec. and its non adjustable.