My car has been running fine for almost two years with k24/18g turbos producing 565AWHP at 1,37 bar...Last month when full throttle from low rpm at high boost the car surges from 4 to 5 krpm and then runs fine...e.g. with 4th gear and 3000rpm when i hit the gas the car starts to accelerate,then surge from 4 to 5 and then goes fine...any ideas?

 

Any codes? First guess is plugs....

 

Any lights blinking? I just had this exact same problem and thought I had an issue. The yellow "info" light was blinking when my car would layover. Try the exact same test with your PSM off. It turned out to be my traction control "helpin" me out.

 

I will plug PIWIS tomorrow to see for codes...imagine that with all surges the car ran a 6,45 60-130 an hour ago...Lets hope it is something simple like plugs...

 

thank you but it happens with psm off...

 

Ok. Then it likely is plugs or coils. Good Luck

 

i think so...plugs...but it is strange that above 5krpm the car runs strong and stable...isnt it?

 

Not really that strange. My would break up at 4k (peak TQ) after that it's OK. Peak TQ is the MOST cylinder pressure, that's why. Blows the fire out. As you rev, pressure goes down (TQ drops off) and no more fire blowing out...At our power level, plugs only last about 5k miles..

 

99% of my driving is done with boost controller off(0,7 to 0,8 bar)...1% is done at 1,37bar...i havent changed plugs for 13000miles so maybe now it is the time...Very good explanation about rpm range...thank you...

 

Change your plugs and inspect your coils for cracks and go have some fun!!!

 

Rep for you my friend...i lll change plugs and try to get to 5sec club...

 

Don't forget to scan it too, just in case!!! Datalog it if you can, and see if it misfires and where, so you know what to look for when you get stuff apart.

 

I think(not sure ) my plugs are Denso IK22...are they ok for that hp application?Which plugs do you use?

 

We prefer NGK BKR7E

 

you sure its not the clutch slipping?