m3 engine not running right after jetwashing

[m3jappa]

basically it sounds like a scooby running on 3cyl.ive taken the coils out and plugs and blown it all out with comp air,ive tried my mates coils too and ive taken the throttle postion sensor off and cleaned it and blown it out,i cant see how any water had got to the ecu either as that part wasnt washed throughly,even the fuse box was bone dry inside.
any suggestions appreciated

[r5gttgaz]

Have you soaked everything in WD40?

[m3jappa]

no but i used some brush on gunk to clean up the engine bay and jetted it of now it sounds like a real dog and wont rev/run properly

[r5gttgaz]

Get all the electricals soaked in WD40 and try again.

[m3jappa]

ok cheers mate will do,thanks

[naetype]

The ECU (or DME in BMW speak) sits in a wee cubby hole which can get filled up with water, particularly after a car/jet wash and when the drainage holes get blocked. It sits behind the expansion tank.