Idle troubles
Thread Starter
Launching!
Joined: Nov 2002
Posts: 218
Likes: 0
From: Houston
Idle troubles Hey guys, I need some help once again. The car i 
dles fine up to about 180 - 190 degress, at which point it starts to studder like its about to die, then the idle usually smooths out when the thermostat opens. Once it hits about 200 degrees, it will idle fine, but as soon as I give it any gas manually it stalls and dies. Also, the fans will not come on. Ive checked the fan relay and its good. Any ideas?
dles fine up to about 180 - 190 degress, at which point it starts to studder like its about to die, then the idle usually smooths out when the thermostat opens. Once it hits about 200 degrees, it will idle fine, but as soon as I give it any gas manually it stalls and dies. Also, the fans will not come on. Ive checked the fan relay and its good. Any ideas? Re: Idle troubles Check for any air leaks on the intake, especially past the MAF, as well as the intake itself. If you spray some carb cleaner around areas you suspect and the rpm jumps, you have a leak.
How is the car at WOT?
How is the car at WOT?
Thread Starter
Launching!
Joined: Nov 2002
Posts: 218
Likes: 0
From: Houston
Re: Idle troubles It seems to run fine at WOT. Keep in mind Im still running open hearders and the car isnt technically on the road yet, so its a little loud to diagnose problems at high RPMs.
Launching!
Joined: Dec 2001
Posts: 259
Likes: 1
From: Durham, NC
Re: Idle troubles I'm still battling this problem with my car. Cold, runs fine, hot, runs like crap.
I drove it around for a few days with the O2s disconnected. It runs fine that way, albeit a tad rich.
I then swapped out the O2 sensors, which seemed at first to help. IOWs, when I started the car after swapping in the new set (not brand new, they were the rears that I'm not using), it idled nicely up to 185* or so (like it always has) and then it blurped a few times, fan kicked on, couple more blurps, and then it smoothed out. I thought I was golden. So, next day, I drive it. Once up to 185* or so, it starts to misbehave at a stoplight, but not too bad. On the highway, running fine, cruising in 6th at low RPMs, then after a few minutes it started hesitating. Once ever 10-15 seconds it will stutter and lose power. Once, while passing somone, it almost seemed like it backfired ??? Just sorta choked up and made the car lurch.
I dunno about WOT - I'm still too chicken to try that - I'm guessing it'd be fine as it seems to be fine at about 75% throttle.
Car is only just now back off the jackstands (had a damn blown wheel bearing 0 had to get a new hub). Little fearful that there are still some gremlins lurking.
I'm completely puzzled by this. I tried to perform the Idle Learn procedure. Motor was cold. I guess I should try it do it again. This sucks. Seems like with a vac leak it would run just as bad cold as hot, with O2s or without. I think I definitely have an open loop situation. O2s look clean (ones I pulled out were black).
I drove it around for a few days with the O2s disconnected. It runs fine that way, albeit a tad rich.
I then swapped out the O2 sensors, which seemed at first to help. IOWs, when I started the car after swapping in the new set (not brand new, they were the rears that I'm not using), it idled nicely up to 185* or so (like it always has) and then it blurped a few times, fan kicked on, couple more blurps, and then it smoothed out. I thought I was golden. So, next day, I drive it. Once up to 185* or so, it starts to misbehave at a stoplight, but not too bad. On the highway, running fine, cruising in 6th at low RPMs, then after a few minutes it started hesitating. Once ever 10-15 seconds it will stutter and lose power. Once, while passing somone, it almost seemed like it backfired ??? Just sorta choked up and made the car lurch.
I dunno about WOT - I'm still too chicken to try that - I'm guessing it'd be fine as it seems to be fine at about 75% throttle.
Car is only just now back off the jackstands (had a damn blown wheel bearing 0 had to get a new hub). Little fearful that there are still some gremlins lurking.
I'm completely puzzled by this. I tried to perform the Idle Learn procedure. Motor was cold. I guess I should try it do it again. This sucks. Seems like with a vac leak it would run just as bad cold as hot, with O2s or without. I think I definitely have an open loop situation. O2s look clean (ones I pulled out were black).
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Launching!
Joined: Dec 2001
Posts: 259
Likes: 1
From: Durham, NC
Re: Idle troubles I have a brand new IAT installed about 2 inches in front of the MAFT which is about 8 inches in front of the TB.
My coolant sensor seems to work just fine. It reads (via ATAP) within a degree of my Autometer guage, the sender for which is in the pass. side head.
Has anyone else performed the Idle learn procedure with any success?
My coolant sensor seems to work just fine. It reads (via ATAP) within a degree of my Autometer guage, the sender for which is in the pass. side head.
Has anyone else performed the Idle learn procedure with any success?
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TECH Apprentice
Joined: Jun 2002
Posts: 319
Likes: 0
From: NH
Re: Idle troubles I performed the idle learn procedure. Since then the car fires right up and idles and I can stab the throttle and I get excellent throttle response. I still get a very low rpm almost to the point of stalling everytime I come to a stop where the rpm's drop relatively quickly, at closed throttle. It always recovers though. I think it is related to my 4:56 gears with a PCM who thinks they are stock. Couple of wot runs down the street yesterday and I got a big dip in the power on the 2nd to 3rd gear shift around 5000 rpm. Almost like fuel starvation. I wonder if my 3/8" fuel feed with 5/16" return line is going to bite me in the ***?
Re: Idle troubles Just disconnect power to the PCM, reconnect fuses and let it idle and when temp is at least 176F for 5 minutes. Shut off engine for at least 30 seconds and you're good to go.
Launching!
Joined: Dec 2001
Posts: 259
Likes: 1
From: Durham, NC
Re: Idle troubles I didn't change anything. BUT, now it is back to doing the same old crap. I pulled the PCM fuse and did the Idle Learn again, but that didn't fix anything.
The car does get hot. I think I have a shaky low speed fan connector. It goes up to 205* or so at a stoplight and then I can hear the fan turn on. But that must be the high.
I dunno, Like I said before, it runs fine when cold and with the O2s disconnected.
Strange that it ran well for just the one day (with O2s connected). It's worse when I go to part throttle - it'll stumble and choke. It rarely seems to stumble if I get on it. If I putter around with the throttle barely cracked open, it'll buck like crazy.
The car does get hot. I think I have a shaky low speed fan connector. It goes up to 205* or so at a stoplight and then I can hear the fan turn on. But that must be the high.
I dunno, Like I said before, it runs fine when cold and with the O2s disconnected.
Strange that it ran well for just the one day (with O2s connected). It's worse when I go to part throttle - it'll stumble and choke. It rarely seems to stumble if I get on it. If I putter around with the throttle barely cracked open, it'll buck like crazy.
Thread Starter
Launching!
Joined: Nov 2002
Posts: 218
Likes: 0
From: Houston
Re: Idle troubles Is it throwing any codes at all?? I havent put a scanner on mine yet, but Im very curious to find out what your problem is because it sounds very similar to mine.
-Gordon
-Gordon
Launching!
Joined: Dec 2001
Posts: 259
Likes: 1
From: Durham, NC
Re: Idle troubles No codes. Ran like crap all day yesterday. Then this morning it ran great. I just do not understand. I heard a noise from my pump - I think. Some kind of whine from the back. Fuel gauge (which is a 0-90ohm unit, sender is apparently 40-250ohm, damn fsm) was freakin out too. It read 1/2 (= empty) then 3/4, then full, back again. Wierd. So, I put some gas in. I dunno if that means anything at all. Whine seems to have gone away after about a mile and it ran beautifully all the way to work.