sciroccor

Hi. I have an E63 wagon (yes! totally cool!) 2007. two days ago we had flash floods here and they were killer. anyway, I hit a rather large puddle going way to fast (it broke my bumper and part of the undertray) and now my car sounds like it has a supercharger under the hood. it's clearly engine speed based as it changes frequency based on the motor speed not vehicle speed. I am worried if this is more than dirty belt/pulley thing, if somehow water go into the power steering pump or something equally as stupid and baffling. anyone know? my old e500 wagon made this noise too but I always assumed it had something to do with the transfer case. as this car has no transfer case, it's not the same noise or that wasn't the source. again, does anyone know and can tell me what is the source?? please?

Forrest Gump 9

First thing I would check to see if the air filters are wet. Make sure the engine didn't suck any water in. Compression check would be high on my list too.

sciroccor

good points!!! i'll check out the filters. i'll do it now!

O-55

It's probably one of your pulleys (bearings). I would check the A/C pulley first, since it sits the lowest, and move up from there.

nanayaw6

^^ What he said. Though I have a kompressor, my car recently had a similar sound except the car was in park and neutral where the S/C clutch isn't engaged. Turned out to be the bearing inside the AC compressor pulley. Listening from the top, I thought it was my power steering at first till I listened to it with the stethoscope while I had the under tray off. Swapped the compressor and my car is quiet again.

sciroccor

ah, they are dry, dry, dry. nothing at all intake tract. i'll jet some wd40 on the pulley bearings one at a time to investigate that. that's a good call, too. glad it wasn't water in the intake! phfew!