marlinspike

My brother drove his 540i through what apparently turned out to be a deep puddle on the interstate. Ever since then it sounds like a baseball card in bicycle spokes. The sound is speed sensitive and goes away when you put on the throttle, but only if the car is in gear (i.e. the noise is present whether the throttle is on or not in neutral). It's hard to pinpoint the location, but I think it's coming from the front of the car, or front half.

White Devil

Youll probably need to hit Bimmerfest for the answer, maybe a partial hydrolock, or some of the water got into the intake (not bloody likely with the stock intake)...

http://www.bimmerfest.com/forums/sho...d.php?t=342032

trickyricky

Maybe hitting the puddle loosened the radiator fan shroud which actually goes around the whole fan. I would first check anything that broke or moved. Car is auto right? CEL came on? Does it rive fine?

gameoverr96

start the car and look at all moving parts maybe around all parts that are belt driven and look for anything touching.. diagnosing noises are always the hardest to do.. my guess is maybe some of the splash gaurds in the wheel well came loose and maybe rubbing against a pulley or belt

marlinspike

It's an auto. Def not coming from the engine and def not hydrolock. Here's the weird thing - it made the sound quite loudly driving in reverse. Drove inn reverse a few times, and now the sound is gone. Visual inspection reveals nothing out off the ordinary.

trickyricky

My thought is that maybe something got loose or knocked off its place, noise didn't go away in neutral but once in gear and at speed it did, the engine moves as you move the tranny from d to n and r. I would still look for something that his car is now missing, splash guards are a good suggestion as well. If it was hydrolocked, partial or not, there would have been no doubts