[BimmerNugget]

Vehicle:

2011 N51 328i RWD, 60,XXX miles

Symptoms:
-Groaning sound only when cold (Under 60 degrees F)
-Groans in Park, Reverse, and Drive. But the groan is loudest when in reverse.
-Groaning in Park or Drive is very minimal.
-Groaning goes away after driving literally 40-50 feet. (Think a semi trailer length)
For example, I back out of parking spot and its groaning, I put it into drive and move forward 50 feet. Put back into Reverse and it doesn't groan.
-GROANS THE MOST WHEN IN REVERSE AND TURNING STEERING WHEEL.
-Does not groan when car is warm.


Video:

[jt335i]

Doesn’t sound like anything abnormal to me. If you are not getting any strange CELs or notice any smoke or burning smells then your car is fine. If I hear it right, sounds like some kind of mild rattle in the engine bay because a load is on the engine causing it to shake or vibrate a little more. I notice that when my car is in reverse, as opposed to D or N, it tends to have a little vibration and when it is not yet up to normal operating temperature.
As for the steering, when your car is not moving and you turn the steering wheel, the power steering is working harder thus putting a load on the engine. If you have ever driven a car without power steering, you will notice when not in motion how hard it is to turn the wheel versus when the car is in motion.
I could be wrong, but if the groaning or rattle sound gets progressively worse and worse over the next few months take it to a BMW specialist and have them check it.

[MysticRob]

You know enough to film the car and upload the video to youtube, then post it here, so go a bit further and have someone do whatever causes the noise while you hang close by with the hood open so you can localize and diagnose. Sounds like just about anything at this point.

[BimmerNugget]

Originally Posted by MysticRob

You know enough to film the car and upload the video to youtube, then post it here, so go a bit further and have someone do whatever causes the noise while you hang close by with the hood open so you can localize and diagnose. Sounds like just about anything at this point.

I've tried to locate it but couldn't. Here's the strange thing, when I pop the hood and try to locate the sound, i don't hear much groaning. I hear more groaning when standing next to the door/side mirror. What could possibly be near the front door/mirror that could cause this groaning sound.