Bmw 335I Problems Humming in car. Goes away when

Is your oil level or radiator coolant level low? It sounds like the engine is going into "Limp Home" mode to save the engine.

HI THAT HAS NOTHING TO DO WITH THE WATER DRIPPING I WOULD FIRST CHECK THE SUNROOF DRAINHOLES

Switch the front tires and see if it pulls the other way. It shouldn't be pulling at all

check the c.v axle for n.e kind of ware or if it has n.e kind of slack.it maybe going bad.

jack car just enough to take the weight off the road wheel, then using a tyre iron, see if theres any movement in any bushes,only try this on the flat with bricks under the chassis frame just in case....

One in boot on the right hand around the battery somewhere, one under dash and could also be one under the bonnet, would be over to the left hand side of the vehicle. Not had to touch the electrics on any of these yet but generally thats where they hide.

I have a 2007 335i convertible.. my low oil light went on.is there a dip stick or something. how do i tell how low iam

It should be in the boot under a panel on the right hand side

I had a similar problem, when turning to the right or on a right curve, the noise would go away. After some research I found it was the left wheel bearing assembly. I replaced it and the problem is gone. Therefore, check the wheel bearing assembly. You may have to replace it.

Wheel bearings.
For quickly ruling out the CV Joint, in a parking lot, turn one way in a sharp circle, then the other way circle sharply. A clicking sound is indicative of a bad c/v joint or 1/2 shaft.
Humming while in motion (most of times it will only occur during a specific speed range - over a certain speed goes away) says a wheel bearing is shot.
Normally you should replace both at the same time... however you can check with a laser temp gauge each front hub after driving. The hotter one is bad - or a less scientific approach is to swerve going down the road. and listen for an decrease in noise going in one diretcion over the other.
If you are turning the steering wheel right, and the noise goes away, the right bearing is bad and vice versa.

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