after i clean my engine bay it bogs or hesitate to boost when it hits boost... it falls from 4K RPM to 2.5K RPM and after that it's fine all the way to redline...what could of cause this...i did wash the engine bay just wipe and spray black restore on the rubber parts... after that this happen when it hits boost???? it's all stock 05 evo....any ideas???

 

anyone ever have this problem????

 

It falls from 4k to 2.5k? I think you mean it jumps to 4k then falls back down, which means your clutch is slipping.

 

+1

 

or your maf sensor got wet

 

it might very well be a slipping clutch. If it is totally isolated to car wash days, then the MAF might have gotten wet.

Ever close the hood too hard with the engine running, and it stumbles? There you go.

 

There's also a chance that your spark plug tubes have water in them causing the ignition to missfire under load.

Any codes ?
.