Intermittent high idle
Intermittent high idle So I recently got mto car all back together after a heads cam swap. I'm running prc 2.5 heads and a tsunami v2 cam 235 240 .618 .615 111lsa. Now before I even started the car I had the computer flashed with a base file just so it would be more safe to drive to my tune and make sure everything was ok. I noticed after the car got hot if I turned it off then restarted it it would idle fine at about 900rpm, but as soon as I touched the gas it would hang at 1500. It would take about 30 seconds to drop down then do the same thing after hitting the gas. I figured when I got the car tuned it would be fixed, but I got it tuned yesterday and the car made great power and had the same issue. I called them and said something about it they said change out the tps and if that doesn't work it out to bring it by. I changed the tps last night and it seems to be ok, I took it for about a 45 min ride one way tonight shut it off then came back to a buddies shut it off and then on to go home and all was ok. Went to put gas in it stared it and now it's high idleing
This is what I went through. VE in the idle range is off, probably need to relearn your TPS/IAC. Idle airflow adder is probably very high also.
If it does it mainly while coasting, there is a setting that comes on at 2mph and off at1mph I can't think of name but I know where on the screen in hptuners. Make those numbers 82 and 81
If it does it mainly while coasting, there is a setting that comes on at 2mph and off at1mph I can't think of name but I know where on the screen in hptuners. Make those numbers 82 and 81
Intermittent high idle So I recently got my car all back together after a heads cam swap. I'm running prc 2.5 heads and a tsunami v2 cam 235 240 .618 .615 111lsa. Now before I even started the car I had the computer flashed with a base file just so it would be more safe to drive to my tuner and make sure everything was ok. I noticed after the car got hot if I turned it off then restarted it, it would idle fine at about 900rpm, but as soon as I touched the gas it would hang at 1500. It would take about 30 seconds to drop down then do the same thing after hitting the gas again. I figured when I got the car tuned it would be fixed, but I got it tuned yesterday and the car made great power and had the same issue. I called them and said something about it they said change out the tps and if that doesn't work it out to bring it by. I changed the tps last night and it seemed to be ok, I took it for about a 45 min ride one way tonight shut it off then came back to a buddies shut it off again and then back on to go home and all was ok. Went to put gas in it started it and now it's high idleing, I jumped on it in 1st gear and that straightend it out, it was fine the whole way back. I don't really wanna bug them again right away because I feel as if it's something on my end that's wrong. Maybe my iac valve is bad or the auto zone tps is garbage. I haven't checked for vacuum leaks but if that was it, I feel as if it would be a constant problem and not intermittent. Thanks for any help in advance
It happens stopped just the same as it would rolling I can sit there stopped and have it idle fine tap the gas it it goes back up and hangs. Is there an easy way to relearn them, the car also straightend itself out after a short 1st gear WOT pull then was ok the whole way home. Since it happened before the tune and after I feel like the tune is ok. They are happy to look at it again but I won't be able to get there until next Wednesday. So I wanna see if I can try and few things to resolve it.
Base Airflow is way too high under the idle tab. You need to run the Russ K idle config file on a cold startup. Watch for the desired airflow and put those values in. Too much airflow causes all the issues you describe.
Been fighting exact same thing since April. It only happens on initial startup. After 30 sec to min it stops. Then every time I let off the throttle coming to stop it surges between 300-1200 rpm. We messed with the tune countless times but its kinda hard to fix hang & low rpm dip at same time- one fix makes the other worse. I have changed almost everything, even went to cam with less overlap. All brand new parts and nothing but aggravation..
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From: SV, AZ
This is what I went through. VE in the idle range is off, probably need to relearn your TPS/IAC. Idle airflow adder is probably very high also.
If it does it mainly while coasting, there is a setting that comes on at 2mph and off at1mph I can't think of name but I know where on the screen in hptuners. Make those numbers 82 and 81
If it does it mainly while coasting, there is a setting that comes on at 2mph and off at1mph I can't think of name but I know where on the screen in hptuners. Make those numbers 82 and 81
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Verdad Gallardo TECH Regular
Joined: Jun 2012
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From: SV, AZ
Been fighting exact same thing since April. It only happens on initial startup. After 30 sec to min it stops. Then every time I let off the throttle coming to stop it surges between 300-1200 rpm. We messed with the tune countless times but its kinda hard to fix hang & low rpm dip at same time- one fix makes the other worse. I have changed almost everything, even went to cam with less overlap. All brand new parts and nothing but aggravation..
And I am learning. Quite a bit.
What would be more helpful would be to explain how the table works, why it's there, and how best to tweak it.
Without seeing the tune and a log everyone is just guessing. It could be one table off or you could have 5 or 6 tables off causing it. Having the base airflow to high is what I see the most of but it could also be other modifiers are wrong adding airflow or a delay to that. There isnt a set value that works for each setup and one set of number smay work perfect on car and then the next may not even idle with the same values.
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From: SV, AZ
No need to be rude. i'm not some troll repeating stuff I read. I had to do it on my car to get it to stop idling at 1800 rpm before reaching a dead, complete stop, at which point it returned to 800.
And I am learning. Quite a bit.
What would be more helpful would be to explain how the table works, why it's there, and how best to tweak it.
And I am learning. Quite a bit.
What would be more helpful would be to explain how the table works, why it's there, and how best to tweak it.
Without seeing the tune and a log everyone is just guessing. It could be one table off or you could have 5 or 6 tables off causing it. Having the base airflow to high is what I see the most of but it could also be other modifiers are wrong adding airflow or a delay to that. There isnt a set value that works for each setup and one set of number smay work perfect on car and then the next may not even idle with the same values.
TECH Regular
Joined: Jun 2012
Posts: 414
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From: SV, AZ
Been fighting exact same thing since April. It only happens on initial startup. After 30 sec to min it stops. Then every time I let off the throttle coming to stop it surges between 300-1200 rpm. We messed with the tune countless times but its kinda hard to fix hang & low rpm dip at same time- one fix makes the other worse. I have changed almost everything, even went to cam with less overlap. All brand new parts and nothing but aggravation..
I haven't done a more test yet I will this weekend. Idk about needing a new tuner, because I feel this is unrelated to the tune because the car did it a few times before I had it tuned. So the problem was there, I figured because it was untuned. Plus the car made 448 and 407 with the setup stock ls6 intake and stock bottom end. They are going to look over the next Wednesday if I can't fix it this weekend.
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Joined: Jun 2012
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From: SV, AZ
Making WOT power is easy. I can teach you in 15 min. It's the part throttle, off idle, driveability stuff that separates tuners and "tooners". Good luck.
Last edited by eaglegoat; Aug 21, 2015 at 10:08 PM. Reason: Spelling
As for me and my car, I just gave up and unplugged the IAC. Other than cold start issues (like a carb'd car now..lol) I'm thrilled to have a consistent rock solid idle and driveability with a 236/242 cam.
I became so frustrated browsing forums and trying again and again that I needed a break. I keep telling myself that someday when I get time I'll plug in the IAC and start over...but as for now it's too much fun to drive as is.
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Joined: Jun 2012
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From: SV, AZ
I bow to those who can fix intermittent high idle. I wish someone would post a guide on fixing this issue rather than the usual chorus of "your VE tables suck" and "Run the Russ K idle config" and "Check your timing" and "base running airflow warble garble". Well....duh. Given the complexity of HpTuners and the factory PCM it seems to go a little deeper than the usual condescending advice.
As for me and my car, I just gave up and unplugged the IAC. Other than cold start issues (like a carb'd car now..lol) I'm thrilled to have a consistent rock solid idle and driveability with a 236/242 cam.
I became so frustrated browsing forums and trying again and again that I needed a break. I keep telling myself that someday when I get time I'll plug in the IAC and start over...but as for now it's too much fun to drive as is.
As for me and my car, I just gave up and unplugged the IAC. Other than cold start issues (like a carb'd car now..lol) I'm thrilled to have a consistent rock solid idle and driveability with a 236/242 cam.
I became so frustrated browsing forums and trying again and again that I needed a break. I keep telling myself that someday when I get time I'll plug in the IAC and start over...but as for now it's too much fun to drive as is.