Ok just noticed this. I have an Evo IX MR with the Works T340 kit. So it has 269cams. Car idles like stock. When I am up to temp and stopped at a light the idle will rise to about 1100 rpms then will dip back down to 800 then up to 950. sometimes the rpms will rise to 1300.

I don't feel like I have a boost leak car runs normal and strong. The works tune is very conservative so IDK any thoughts on where I can look?

 

Bump Anyone.

 

Mine did this for a while. I found that reducing the gap on the plugs helped to make it far less than it was. Believe I set them at 25 or some such maybe a bit less. If you plugs are old it helps to just replace them, check the gap though.

I think it's the cams that cause it because mine didn't do it until I installed mine. I have the mild 264/272 HKS FWIW.

 

I am going to try and change the plugs tomorrow and see if it helps a bit. Probably due for a change anyway.

 

How are you tuning the car, You can adjust the Accel Enrichment and this will help. Also with those cams base idle will need to be increase or the car kinda searches for the right idle speed.