[F30FromTexas]

The entire exhaust system from the manifold to the muffler tip vibrates on my 2013 F30 with 34k miles. It has gotten progressively worse in the last two months. The dealer said they didn't find anything wrong with it and nothing is loose but it has gotten to a point to where I can feel the vibration inside of the car now. Looking under the hood with a flash light shined at the flex pipe coming down from the manifold its easily visible that its vibrating. The muffler tip will sometimes rattle as well. My warranty has just expired and I'm not sure what to do to remedy this. Anyone have any idea of what it could be? Would a tune and down pipe help?

[cfm56d7b]

Do you detect any unusual engine or transmission vibrations? The exhaust is the tail end component and could be a symptom and not the root cause.

[F30FromTexas]

The engine and transmission seem to be fine. On a cold start it has gotten progressively louder and the noise I'm referring to is definitely not the injectors. The other day I got underneath the car while it was idling and probed the exhaust with a broom stick to get a feel of the vibration coming from the exhaust and its pretty bad. I'm certain that is the same vibration that I'm now feeling inside of the car.

[F30FromTexas]

I've figured out that this vibration only occurs when the ac compressor is running. The noise and vibration are night and day different when its running. Are there any signs to look for when the a/c compressor is failing? Or could it be the belt tensioner in the serpentine system?

[cfm56d7b]

Originally Posted by F30FromTexas

I've figured out that this vibration only occurs when the ac compressor is running. The noise and vibration are night and day different when its running. Are there any signs to look for when the a/c compressor is failing? Or could it be the belt tensioner in the serpentine system?

If this is the root cause, your local dealer should have been able to determine it during the last service visit. Do you have another dealer nearby to visit?