Idle Surge Help
08-19-2007, 02:18 PM
#1
Idle Surge Help I've been trying to get the idle to not surge so much, i have a baby 226/226 cam and i cant get the idle to stay calm. It will calm it self out for a few seconds then start hunting again then calm down again, both in gear and park. Also when I'm idling around the parking lot (not steping on the gas) the car will want to take off and then fall on it's face and take off and fall again, sometimes diping into 345 RPM's (i have it set to 850) I've played with my RAF but I'm lost to where else to go. I'm using the tut in the sticky up top but dosnt really say anything about how to fix it. Right now I'm on a SD tune with a LC1 wideband. My IAC valve works, at around 104 steps in gear and 55ish in park, it's just when it starts to act up it goes all over the place. Anyone have any idea's? Using HPT. thanks!
08-19-2007, 03:12 PM
#2
Here's the easiest fix known to man. Hook up your scan tool and monitor TPS.With the battery on, adjust your idle screw to about 3-4%. Turn the car off and unplug your TPS sensor, then turn the the key on, but don't start the car for about 5 sec. Turn the car back off and plug the TPS back in. Turn the car back on, and the TPS reading should be 0-.4. I got this from a thread a couple years ago called Stop Drilling Those Throttle Bodies!!!. I gave the Reader's Digest version of it, do a search on that title if you want the full read.
My car was surging 1K+ before the re-learn, and only surges ~100 after. I could probably spend the time to get it exact, but it was such a good and easy fix I can deall with a 100 rpm surge.
My car was surging 1K+ before the re-learn, and only surges ~100 after. I could probably spend the time to get it exact, but it was such a good and easy fix I can deall with a 100 rpm surge.
08-19-2007, 03:36 PM
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Originally Posted by jmill96Z
Here's the easiest fix known to man. Hook up your scan tool and monitor TPS.With the battery on, adjust your idle screw to about 3-4%. Turn the car off and unplug your TPS sensor, then turn the the key on, but don't start the car for about 5 sec. Turn the car back off and plug the TPS back in. Turn the car back on, and the TPS reading should be 0-.4. I got this from a thread a couple years ago called Stop Drilling Those Throttle Bodies!!!. I gave the Reader's Digest version of it, do a search on that title if you want the full read.
My car was surging 1K+ before the re-learn, and only surges ~100 after. I could probably spend the time to get it exact, but it was such a good and easy fix I can deall with a 100 rpm surge.
My car was surging 1K+ before the re-learn, and only surges ~100 after. I could probably spend the time to get it exact, but it was such a good and easy fix I can deall with a 100 rpm surge.
08-19-2007, 10:36 PM
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Originally Posted by reject
I have already gotten that one done, i think i'm pretty close to the limit voltage wise, any other thing else you can think of?
SSpdDmon i'm using HPt
SSpdDmon i'm using HPt
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08-19-2007, 11:00 PM
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Originally Posted by reject
i'll try some of those things tomorrow morning, thanks!
I had the same problem and tried just about EVERYTHING.
I found this thread and followed it exactly and it idles perfectly now:
https://ls1tech.com/forums/pcm-diagnostics-tuning/259032-how-tune-idle.html
08-22-2007, 11:34 PM
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I am still learning so don't take this as gospel, but it seems alot of it is in the spark. Make sure that your Idle Adaptive Spark Control table is set at -8* across the table (anything other than that made my motor surge) and make sure that your ECT spark multiplier is set to 0 for the idle range (0-1600 rpm).
Post up a log of your idle and also post up your tune. Someone is bound to chime in on what it might be. Log what you timing advance looks like.
Post up a log of your idle and also post up your tune. Someone is bound to chime in on what it might be. Log what you timing advance looks like.
08-23-2007, 07:43 PM
#12
here's the tune and log files
tune
http://reject.sleepingz.com/HPT/SDTune10.hpt
log
http://reject.sleepingz.com/HPT/idle%20log.hpl
tune
http://reject.sleepingz.com/HPT/SDTune10.hpt
log
http://reject.sleepingz.com/HPT/idle%20log.hpl
08-24-2007, 08:30 AM
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Play with it and see what it likes. That should be ok though.
Look at the cells around your idle cell. I'm at work, so I can't look at your tables. When you step into the throttle, what does the AF do?
Look at the cells around your idle cell. I'm at work, so I can't look at your tables. When you step into the throttle, what does the AF do?
08-24-2007, 11:08 AM
#16
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The one thing I noticed was that your spark at idle was kinda all over the place. Here is what mine looks like:
Try that and see what happens. Next, I would take a look at your VE tables when at idle. Make just one change at a time so you know what works and what doesn't.
I could not read your log file. Must be the version I'm using or something.
Try that and see what happens. Next, I would take a look at your VE tables when at idle. Make just one change at a time so you know what works and what doesn't.
I could not read your log file. Must be the version I'm using or something.
08-24-2007, 06:30 PM
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I got to look at your file...put your OLFA table back to stock and go from there. The OLFA table needs to be tweaked, but not commanding 14.7 everywhere.
Just from looking at your VE table, you are prob going to have to take more fuel out....esp at idle.
Get your park/drive spark tables the same. Add a little bit more timing in idle RPM.
Just from looking at your VE table, you are prob going to have to take more fuel out....esp at idle.
Get your park/drive spark tables the same. Add a little bit more timing in idle RPM.
08-24-2007, 08:46 PM
#19
did alittle loggin and retuned the VE to be around 15.25
left the timing alone becuae i was moving it with the controls threw the logger and everytime i would do a solid 22* the car would act funny like started to turn slower
what i was noticing, when the idle starts going erratic, the MAP drops about 4 or 5 pressure....as if it was picking up extra air for a second then trying to recover.
anyways here's the log
http://reject.sleepingz.com/HPT/idle%20VE%20retune.hpl
and the tune
http://reject.sleepingz.com/HPT/SDTune10%20%20B.hpt
left the timing alone becuae i was moving it with the controls threw the logger and everytime i would do a solid 22* the car would act funny like started to turn slower
what i was noticing, when the idle starts going erratic, the MAP drops about 4 or 5 pressure....as if it was picking up extra air for a second then trying to recover.
anyways here's the log
http://reject.sleepingz.com/HPT/idle%20VE%20retune.hpl
and the tune
http://reject.sleepingz.com/HPT/SDTune10%20%20B.hpt
