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12secformula
December 17th, 2006, 02:54 PM
I'm new to EFILive, I've been reading thread after thread on idle tuning and my head hurts!! I have a 2000 Trans Am A4 with a 222/228, .551/.551 cam on a 115 and a Yank SS3200 converter. After the cam install and idle relearn the car will start up fine, idle fine in park/neutral whether it's hot or cold. Hot restarts are fine also. I don't have any of the "cruise control" effect going on. The only gripe I have is that coming to a stop <at 5mph and under> while the car is warmed up <doesn't do it cold> sometimes the idle will surge <dip then rev>. It will straighten itself out if I come to a complete stop. If I continue to coast/slow down, it will hunt up and down and surge until I stop or it stalls. I have the idle in gear set to 650, and idle in park/neutral at 700. I don't have any surging while driving over 5mph, only when coming to a stop or coasting under 5mph. Where should I start looking in order to correct this problem? From what I read the throttle cracker is what I should be changing? Any info would be appreciated!
Thanks!

Rhino79
December 17th, 2006, 03:06 PM
Try raising your throttle cracker enable/disable speeds to about 10 enable and 9 disable, if that helps then you can blend your throttle cracker airflow table at that mph range so its not such a drastic aiflow dropoff when is deactives the cracker.

Tordne
December 17th, 2006, 03:20 PM
It can also just be error in the Desired Airflow table. To little airflow will cause that also, to much and the RPM will hang high.

Rhino79
December 17th, 2006, 03:30 PM
Idle tuning is definetly the hardest part of tuning, and the desired airflow table is very sensative. I used to try to use the throttle cracker as a crutch for an improperly tuned desired airflow table. Chad at Greenlight helped me learn that with an accurate desired airflow table, most vehicles will not need nearly as much throttle cracker.

12secformula
December 18th, 2006, 03:25 AM
Try raising your throttle cracker enable/disable speeds to about 10 enable and 9 disable, if that helps then you can blend your throttle cracker airflow table at that mph range so its not such a drastic aiflow dropoff when is deactives the cracker.
I tried this and it helped. The car no longer surges and dies when I come to a stop. Do I leave the throttle cracker at this setting and blend at 9-10mph?
Thanks again!

Rhino79
December 18th, 2006, 10:27 AM
Yep that whould do, blend a little at a time to make the transition from say 20 mph to 9 mph as smooth as possible with the value at 9 mph being almost 0. Glad it helped!

12secformula
December 18th, 2006, 12:51 PM
It helped when coming to a stop but now a new problem has come up. When I let off the throttle while accelerating between 5mph and 25mph the rpms will dip down to 500 then bounce back up. The car hasn't stalled yet doing this. Would this be the throttle follower airflow or the decay rate?

Rhino79
December 18th, 2006, 01:01 PM
Try to add a little to the desired airflow like .25 g/sec at a time, but not too much cause it will "cruise" on you. You could probably mess with the throttle follower some, but I'd try this first.