I am having a weird problem with my idle. First of all, my idle fluctuates...I have the target idle set to 1200 but it fluctuates anywhere from 1300 to 1000 and keeps jumping up and down. Second of all, whenever I come to a stop and put the car in neutral, the RPMS drop down below 900 (I have GSC S2 cams) and the engine wants to stall but then catches itself after about 3-5 seconds. Most of the time it doesn't stall but when I am turning right after I put it in neutral, the car stalls(power steering helping to load down the car).

My thought is that the idle stepper motor is not tuned right. Maybe it isn't letting air in as soon as the throttle is closed like it's supposed to. When the throttle is closed, the idle stepper motor is supposed to be open enough to let air in and then slowly close to make the car come down to the idle target smoothly. What I am thinking is that it isn't open enough to let air come through to burn the extra fuel that was added before the throttle was closed causing a stumble and rich AFR. Do you guys have any other thoughts? I can post my cal too if needed.

And my thoughts on the idle fluctuating...I don't know. Any help would be appreciated.


Also...my radiator fan (the one on the right side looking at the car from the front) is weird. Even though the car is cold, it turns on. In the MN winter here, my car never ever warms up unless it is driven. But...even if I do drive it 10 miles from work to home, the top of the radiator is still ice cold!

 

I had this problem too. Resetting the ecu and dicking in ecuflash didn't seem to help.

The last time I reset the ecu I let it idle for probably damn near a half hour the first 2 times I started it after the reset. It's been idling perfect ever since, and I mean like stock perfect. It pretty much solved every idle issue I had, including cold start idling. I didn't change anything else other than that.

 

I'm not on a stock ecu. I am using an AEM EMS. I know what you're talking about though. I had to do the same thing when I was on the stock ecu.

 

i have the same issue but ive noticed that if i let the car warm up for about 20 to 30 min its fine

 

Just needs more tuning. Keep working at it and it will be right

 

Did you get this resolved? I know you got the car retuned already but don't know if this issue is still there. My car idles and drives perfect so let me know if you still need help.
About the fan, you can turn that off in the software.