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View Full Version : Idle learn after cam install


minytrker
March 12th, 2006, 06:11 PM
I just installed heads, cam, and headers in a friends 99 corvette. He bought everything used with very low miles and in perfect shape. The guy he bought everything from is big into racing and performance. He was nice enough to send me a copy of his tune to make sure we could get the car to start. I know every car is differnt but I am new to tuning and never messed with a car with a cam. The car idles great wit hthe a/c on but without it hunts for idle by surging about 100 rpms. Will this go away after some miles or will it need to be tuned out? We have only drove the car about 20 miles.
ringram
March 12th, 2006, 08:32 PM
Check out the stickies and search... This has been covered a lot recently.

http://efiforum.iqd.co.nz/showthread.php?t=149
minytrker
March 13th, 2006, 01:36 AM
Thanks but I already read all that. My question is the car idles great with the a/c on but without it hunts for idle by surging about 100 rpms. Will this go away after some miles or will it need to be tuned out? We have only drove the car about 20 miles.
ringram
March 13th, 2006, 03:22 AM
You can try copying the AC on tables into the AC Off ones, and maybe dropping a little extra off.
TAQuickness
March 13th, 2006, 07:37 AM
The PCM has limits to how much it can learn at idle (similar to fuel trims). If the cam's AC off idle requirements are within the PCM learning range, yes, it will learn over time.

sound like you have a good base tune to start working from. I would take a look at the idle trims and adjust the desired airflow accordingly.
minytrker
April 5th, 2006, 05:27 PM
Alright after about 400 miles of driving and tweaking the car is running pretty good. Next ls6 intake, bigger injectors, and better headers and exhaust. The car now idles fine BUT every now and again it will surge just a little. I have let the car idle for 25 mins straight with no surge, drove it around all day no surge then may pull up to a light and get a little surge. The surge is maybe 100 rpm. The owner is really happy with the way the car runs and says he doesnt care about it since it so rare. I just want to find it for myself. Any guesses?