Need help with high idle
09-08-2010, 08:08 PM
#22
I just got it done, I'll go log it right now. Thanks for the help, I really want to not only fix it but understand what needs to be fixed, if you know what I mean. I spent hours looking at guides, writeups, the help file, etc. And still don't really get how to affect a change towards what I want to do.
EDIT: Just logged it for 10 minutes after changing my alternator.... and now its perfect? Not a hiccup the entire run. I'm going to have to drive it and see if it does anything after I move the car.
EDIT: Just logged it for 10 minutes after changing my alternator.... and now its perfect? Not a hiccup the entire run. I'm going to have to drive it and see if it does anything after I move the car.
Last edited by Arc00TA; 09-08-2010 at 08:20 PM.
09-08-2010, 08:47 PM
#23
Here we go. First log is cold to fully warm, I then drove around my block and came back, and it started acting up again. I logged only a few seconds of that because its the same no matter how long it sits there. I did jab the gas one time, and it takes forever for it to come back down.
09-09-2010, 03:19 PM
#24
You need to log with your stock throttle body attatched. Sounds to me like the throttle body got a little to ported because your IAC shouldn't be 0 at your proper idle. So something is amiss there. If you put your stocker back on and you see 40~90 counts, you know your problem.
09-09-2010, 04:47 PM
#25
You need to log with your stock throttle body attatched. Sounds to me like the throttle body got a little to ported because your IAC shouldn't be 0 at your proper idle. So something is amiss there. If you put your stocker back on and you see 40~90 counts, you know your problem.
Yes, it is fine with the stock one I already tried that and checked the log, it runs between 45-75. So basically there is no way to compensate for it?
09-09-2010, 05:46 PM
#26
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You need to log with your stock throttle body attatched. Sounds to me like the throttle body got a little to ported because your IAC shouldn't be 0 at your proper idle. So something is amiss there. If you put your stocker back on and you see 40~90 counts, you know your problem.
There is something wrong with the new TB as you are getting too much idle air.
Have you tried backing off the throttle stop to close the blade more at idle?
Has the "Porting" job gone too far & affected the clearance between the throttle blade & body?
Is the throttle cable too tight?
09-09-2010, 05:49 PM
#27
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Once your IAC pegs at 0 you have no more control over idle. Fix the mechanical issue first which is causing excessive idle air.
09-09-2010, 05:59 PM
#28
Start car: cold to fully warm idle is GREAT flat at 800 IAC at 0
Drive car: Now it surges at idle and won't come under 1000rpm with fluctuating IAC
Why the change after the car has driven?
The throttle stop is all the way in. I actually checked by covering the IAC port and the throttle blade hole and the car stalls. It is not getting air around the blade. Its a pretty popular throttle body so I don't see that it would have gotten over-ported.
09-09-2010, 06:24 PM
#29
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Ok, this is still confusing me so if you could explain.
Start car: cold to fully warm idle is GREAT flat at 800 IAC at 0
Drive car: Now it surges at idle and won't come under 1000rpm with fluctuating IAC
Why the change after the car has driven?
The throttle stop is all the way in. I actually checked by covering the IAC port and the throttle blade hole and the car stalls. It is not getting air around the blade. Its a pretty popular throttle body so I don't see that it would have gotten over-ported.
Start car: cold to fully warm idle is GREAT flat at 800 IAC at 0
Drive car: Now it surges at idle and won't come under 1000rpm with fluctuating IAC
Why the change after the car has driven?
The throttle stop is all the way in. I actually checked by covering the IAC port and the throttle blade hole and the car stalls. It is not getting air around the blade. Its a pretty popular throttle body so I don't see that it would have gotten over-ported.
You say that when you block the iac port the motor stalls. Yet with the iac at 0 it doesnt. This shows that the problem is in the IAC pintle/seat area as 0 steps should close the passage.
09-09-2010, 08:20 PM
#30
There is a "lost IAC" logic in the PCM that may be tripping when you go for a drive. I cant view your files as I dont have HPT, but the issue is not tune related anyway.
You say that when you block the iac port the motor stalls. Yet with the iac at 0 it doesnt. This shows that the problem is in the IAC pintle/seat area as 0 steps should close the passage.
You say that when you block the iac port the motor stalls. Yet with the iac at 0 it doesnt. This shows that the problem is in the IAC pintle/seat area as 0 steps should close the passage.
Thanks for the help guys, gonna dump the ported one and be done with it.
09-09-2010, 08:55 PM
#31
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If there is try taping over this hole first. You may be able to work around the problem.
09-09-2010, 09:24 PM
#32
The original blade had a hole drilled bigger than stock. I swapped the stock blade in and it dropped about 300 rpm. I already put the stocker back on, I say screw it. My old T/A made 425rwhp just fine through a stock TB, I was just hoping to pick up some easy ponies this time around.
09-12-2010, 05:56 PM
#33
Well I found the cause of the problem today. It has started surging even with the stock TB on. I started my teardown for my turbo build, and the whole bottom panel of my BBK intake was off. All of the screws backed out and were sitting on the valley cover. So, high idle solved.
