Hi guys,

I've got a pretty strange issue with my evo and hoping someone had some insight.

My evo runs great until the engine gets up to temp. After that, only when the SST is in drive/auto, I've got the wildest idling. Drops to almost 0 RPM, stalled a few times.

Strange thing is, when driving with the stick or paddles (semi-auto?) that problem disappears. I recently had it serviced at an evo specialist, they'd never seen anything like it.

I've tried the MAF clean and idle reset, even new spark plugs. No change.

Has anyone seen anything like this?

Also, not sure if it makes any difference but i very occasionally get a p1877 code and second gear is unavailable. Problem seems to go away after restarting the car.

Thanks in advance!

 

did you tell the dealer about the problem ?

 

Bought it privately. The problem wasn't apparent during the test drive.

I've thought about taking it to Autotorque or someone local but was wondering if anyone had a similar issue, praying (but not expecting ​​​​​​) it's an easily fixed issue.

Thanks for the reply.

 

I personally don't have much experience with Evo X/4B11 chassis's.

I've had similar run ins with earlier Evolutions. Cars would run great until up to temp, after that it would hunt and stall out.

The culprit every time was idler air valve

 

Yup, that's my problem.

Doesn't the evo x have an all electronic throttle body? Not sure it has an IACV.

Thanks for the help though mate, I've wondered about taking the throttle body off and cleaning it but a fair few posts I've seen say this isn't really worth it.

Might have to bite the bullet and take it into another Evo specialist.

 

Yeah, the Evo idle is controlled by the electronic throttle vs. an IACV. Some people have idle issues when the radiator fan blows on an unshielded aftermarket intake. Otherwise see what the coolant temp sensor is showing once the car is warmed up. A bad coolant temp sensor can cause all sorts of havoc.