Evo sputtering, evoscan log attached
 

Hi guys,

My Evo 8 was running fine until the other day, the problem started with just one sputter I felt when it was coming on boost. Gradually this problem has progressed to constant little sputters throughout the rev range after hitting boost (and probably before boost but I just can't notice it as much). The problem seems to be better during cold nights and it gets worse after driving it for a while. It is really annoying and the car is not running smooth (used to run like new before this). I have logged it with Evoscan and the ECU isn't giving off any error codes. The exhaust note also sounds much less refined and raspy.

I am running NGK Iridium plugs, I have taken the plugs out and they all look good and consitant. I have tried replacing them with NGK BPR7ES (admitedly without gapping them) and the problem remains.

I have tried new petrol as well, same issue.

I have taken the airbox out and looked for leaks under there but everything seems to be fine.

I have attached an Evoscan log file. I have attached it as a .txt as it didn't let me attach it as a .csv so please rename accordingly.

If you require me to do more logs please let me know what you would like me to do, the attached log is in 3rd gear.

I'm running 21psi of boost on a tuned ECU. I have a 3" exhaust with cat. Apart from this everything on the car is stock.

Thanks a lot in advance for your help guys, this problem is really doing my head in and any assistance will be greatly appreciated.

Pull the catalytic converter off to make sure flow is not obstructed.

Good luck!

Thanks, I'll do it today. What about sensors and stuff like that?

Any more suggestions guys?