[Needsdecaf]

New to the BMW turbo world, but not the turbo world.

The other day it was pretty warm here in NoVA. I was driving with my windows down next to a concrete wall, going up a 8-10% grade, under very light throttle (10-15 MPH through the parking lot). I hear a rattling noise under load, nothing when let off the throttle. Almost sounds like a rattling exhaust due to engine vibration from lugging, but I don't feel anything.

Is this the infamous wastegate rattle?

535, no tune.

[AVIMAX]

Might be the butterfly valve on the exhaust tip. One of the exhaust tips (don't remember which side, but you can look inside the tips to see which one) closes under certain circumstances (engine load, engine speed, etc.). When I had my 335i convertible and drove with the top down, I could hear that thing opening and closing constantly, and it sounded like a loose heat shield rattling.

[ghueser]

Originally Posted by AVIMAX

Might be the butterfly valve on the exhaust tip. One of the exhaust tips (don't remember which side, but you can look inside the tips to see which one) closes under certain circumstances (engine load, engine speed, etc.). When I had my 335i convertible and drove with the top down, I could hear that thing opening and closing constantly, and it sounded like a loose heat shield rattling.

I might be mistaken but I don't think there are any butterfly valves on either of the exhaust tips on the 535i. I don't recall seeing any when cleaning the tips, and checked in RealOEM and none are indicated on the exhaust illustration.

As far as a wastegate rattle, I have not heard anything on my car that I can recall. I wonder if it could be a loose heat shield near the engine that starts vibrating under certain conditions?

[Needsdecaf]

Originally Posted by ghueser

I might be mistaken but I don't think there are any butterfly valves on either of the exhaust tips on the 535i. I don't recall seeing any when cleaning the tips, and checked in RealOEM and none are indicated on the exhaust illustration.

As far as a wastegate rattle, I have not heard anything on my car that I can recall. I wonder if it could be a loose heat shield near the engine that starts vibrating under certain conditions?

I think it might be. I noted that during startup, there is a rattling which dissipates in about 10-15 seconds. Sounds like a loose heat shield. I had it checked out last week but the dealer said they didn't see anything loose, and that it could be the sound of the injectors since they start at 200 bar. Somehow I don't think so.

If it's a loose heat shield, then I'm fine. I just don't want it to be a sign of turbo issues.

[ghueser]

Originally Posted by Needsdecaf

I think it might be. I noted that during startup, there is a rattling which dissipates in about 10-15 seconds. Sounds like a loose heat shield. I had it checked out last week but the dealer said they didn't see anything loose, and that it could be the sound of the injectors since they start at 200 bar. Somehow I don't think so.

If it's a loose heat shield, then I'm fine. I just don't want it to be a sign of turbo issues.

Needsdecaf,

You may also want to check the plastic undertray beneath the car. This stuff is pretty stiff (it looks like a molded fiber composite), and there is a lot of it under the car. The only reason I bring this up is that I recently got a small branch hung up underneath the car and the sound it emmitted back into the car was unbeleiveble. You would have thought I was dragging a boat anchor!

If you have any loose or missing plastic grommets that hold this stuff down, I imagine that it could vibrate. A long shot.....you never know.

[dreamerx5]

Originally Posted by Needsdecaf

New to the BMW turbo world, but not the turbo world.

The other day it was pretty warm here in NoVA. I was driving with my windows down next to a concrete wall, going up a 8-10% grade, under very light throttle (10-15 MPH through the parking lot). I hear a rattling noise under load, nothing when let off the throttle. Almost sounds like a rattling exhaust due to engine vibration from lugging, but I don't feel anything.

Is this the infamous wastegate rattle?

535, no tune.

I am getting the same rattling noise on my 2011 X5 35i. I took it to the dealership several times. After the about five to six times going back and forth with the dealership, they finally figured out that it was coming from the waste gate. Afte test driving three other x5's, my car seemds to make this noise. However, the dealership had the same car as mine with about 10 miles on the car making the same noise. Apparently, this is a normal sound for a $70,000 car.

I think what the dealership is telling me is BS. But not sure what i can do at this point.