I keep my engine bay clean with regular jet washing.
Just apply common sense and don't spray directly at the E-Box.
Imagine the scene........................
Stokey has bought a MK3 16V Anni, and it has an oil leak, who's source was not easily determined. I bagged up all manner of plugs, and modules (Dizzy etc)
I sprayed a de-greaser all over, agitated, and left to dwell.................... Coffee time..........
Started the Donkey, and went to town with the Karcher!
Donkey spluttered almost immediately and then stopped!
Took 2 days to get it going 100% again. B'turd thing! I eventually found some moisture in the main loom on the front of the gearbox. I had wd40'd the plug twice, but had to take the thing apart and allow to dry overnight.
Still needed to be done to find oil leak.