Idle issue - very lean, weird STFT
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From: Gatineau, Quebec, Canada
Update/bump:
The front o2 was changed this morning, I haven't driven the car much since then but it seems like it might be better, but the idle still stumbled a bit. I'll give the car a chance to re-do the fuel trims and see how it goes.
The front o2 was changed this morning, I haven't driven the car much since then but it seems like it might be better, but the idle still stumbled a bit. I'll give the car a chance to re-do the fuel trims and see how it goes.
my car does this same thing! i have had it retuned a couple of times and it still does it. the clicking from the engine bay sounds like it can be your BCS going insane? mine is wicked loud.
my car has those idle problems when stopped as well especially when i push the clutch in fast
also when the car is cold my idle stays at about 2k until it warms up a bit....very strange...when i get it tuned with tephra it does this...when my other tuner tuned it i didnt have these problems...
my car has those idle problems when stopped as well especially when i push the clutch in fast
also when the car is cold my idle stays at about 2k until it warms up a bit....very strange...when i get it tuned with tephra it does this...when my other tuner tuned it i didnt have these problems...
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From: Gatineau, Quebec, Canada
Update:
Drove in traffic this morning, fuel trims should be stabilized. The car is quite a bit more manageable to drive now, but the idle still dips a bit, though not as much as before. Doesn't look like it's my first time driving stick anymore!
As mentionned though, it's not perfect yet. I did a boost leak test 2 or 3 weeks ago after replacing leaky TB shaft seals, there weren't any major leaks (pressure was very slowly dropping, but that was likely the coupler from the boost leak tester not being perfectly airtight). I may try to take out the IAC motor and give it a bit of a cleaning.
Still open to other suggestions! I can get a video of how the car behaves now if anyone wants.
Drove in traffic this morning, fuel trims should be stabilized. The car is quite a bit more manageable to drive now, but the idle still dips a bit, though not as much as before. Doesn't look like it's my first time driving stick anymore!
As mentionned though, it's not perfect yet. I did a boost leak test 2 or 3 weeks ago after replacing leaky TB shaft seals, there weren't any major leaks (pressure was very slowly dropping, but that was likely the coupler from the boost leak tester not being perfectly airtight). I may try to take out the IAC motor and give it a bit of a cleaning.
Still open to other suggestions! I can get a video of how the car behaves now if anyone wants.
definetly get your IAC cleaned and do the test to make sure its clicking as it should when idle... im assuming since you did the TB shaft seals you already cleaned the TB out. also when you replace o2 sensor, i hope you reset the ecu. also what is your target stopped idle and driving idle rpm?
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Yea, TB was cleaned up when the seals were done. We did did reset the ECU when the o2 was changed to reset the trims, but they reset anyways when I reflash the car. Target RPM is 1000.
now since u replaced ur tb shaft seals, one thing im curious is if you reset the throttle body to the correct setting when you put it back together...other then the IAC being bad, or a possible clogged injector...??? i dunno, have u tried replacing ur maf gasket??
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It did it before the TB seals were replaced, so the TB should be correctly reinstalled. Haven't cleaned or looked at the MAF, heck I'm not even sure where it is besides that it's on the intake pipe.
I have this problem too. Replaced the front O2. Checked the IAC. Clicks/moves and passes resistance test (30ohms). It also does not turn which is supposed to check for the teeth going. Checked for boost and vac leaks. Car went from running fine to severe idle hunting then stalling at idle. This sucks...
Last edited by chmodlf; Sep 30, 2010 at 04:39 PM.
Facing similar problems here!
During idling, my AFR runs from rich (9.9) to lean (21.0) back and forth (like some disco lights on my AFR meter). I did a boost leak test last week and everything is normal. I'm wondering if it has got anything to do with my injector settings but very much doubt so.
With SAS activated, I'm hovering around 750rpm which should be the norm (though I've read that some recommend for 850rpm.
During normal driving and when I come to a stop, rpm sometimes drop between 600rpm to 700rpm. The problem begins when I do spirited or hard driving where the car just stalled when I clutched in.
During idling, my AFR runs from rich (9.9) to lean (21.0) back and forth (like some disco lights on my AFR meter). I did a boost leak test last week and everything is normal. I'm wondering if it has got anything to do with my injector settings but very much doubt so.
With SAS activated, I'm hovering around 750rpm which should be the norm (though I've read that some recommend for 850rpm.
During normal driving and when I come to a stop, rpm sometimes drop between 600rpm to 700rpm. The problem begins when I do spirited or hard driving where the car just stalled when I clutched in.
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From: Gatineau, Quebec, Canada
Atleast I'm not the only one who appears to have an issue like this. Hopefully with all of us working together and sharing what we've tried and what's worked we can get to the bottom of this!
I'll take out the IAC motor this evening to check it out.
I'll take out the IAC motor this evening to check it out.
Right now my afrs are really lean at idle (20+). The car is pretty much undriveable. Good thing I have another car to get around. Are any of you guys also running tephra v7? I am reasonably sure that it is something physical but just trying to get as much info as possible.


