yup its ur MAF, something is up with the MAF sensor, it may have been damaged as the others said.

i recommend switching ur MAF with another Evo and give it a go.

 

Hehe... I'll have to learn to follow you guys more.

I did double check the connection after your suggestion the first time, and I couldn't see how I could've damaged that. I'm always very careful with this car, but I guess it's really easy to damage the MAF.

I'll let you guys know if another MAF fixes the problem.

Thanks for the help

 

I finally tried my friends MAF sensor tonight, but it didn't make any difference. My car was still idling around 1000-1100 RPM fully warmed up.

I'm going to use the voltmeter to check the wiring harness this weekend.

 

I wasnt able to check the wiring harness. I dont have anything to be able to measure the voltage in that small little wire connector.

This thing is really driving me crazy. I'm almost to the point of taking it to the dealer, but I know it must be something simple. Do you guys still think its the MAF sensor even though I swapped it with another Evo 8?

What else could cause that? It idles at the correct speed while its cold, going by the Target Idle RPM and actual RPM. Once the target goes below about 950, the actual stops going down. The ISC steps are down to 0 at that point. When the AC is running, the car idles pretty close to 850.

If I post logs of AFR, O2 sensor, and everything else, would someone be able to better figure out the idle issue?

Thanks,
Mike

 

lol my car is doing the samething as yours. Im even on a stock airbox checked all the wiring dont see anything damaged in the wiring i cleaned all the contacts off at the plug and used dielectric grease.
Ive also noticed when its colder out (I live in fl ) It will idle a littler higher maybe its rom related.