x3 Exhaust 2008 - BMW Forum

Brett7585 · 02-23-2010, 07:55 PM

Anyone have any thoughts on a new muffler or exhaust for an 08 x3? Problem is the inside the right tailpipe there is a valve that opens and closes for backpresser etc at different revs. If i replace the muffler what do i do with the device that controls the valve seems like it may be an air line. Like if i cut it will i get a check engine light or anything? see pic

Thanks for the help!

drz · 02-23-2010, 08:05 PM

Just let it be. Remove it, move it off to teh side, anything really. If you don't believe me, then just remove it, turn on the car, and see if the CEL comes on.

Brett7585 · 02-23-2010, 08:07 PM

Thanks.. Do you know its actual purpose other than to control the valve.. is it nessecary for the engine to operate healthy? or just for noise control

drz · 02-23-2010, 08:17 PM

Just noise control.

Now that I think about it, the flap is vacuum controlled. So, just make sure not to create a vacuum leak -- seal up the hose end tightly. I recall that many people use a golf tee. Google golf tee mod BMW, and you will see that this is very common either to leave the flap always open on the stock exhaust, or when installing aftermarket exhausts.

Good luck!

Brett7585 · 02-23-2010, 08:33 PM

I looked it up seems like a good idea.. but i could not find any instructions.. any ideas on where to find that? is it literally sticking a golf tee in the end of the hose? should i wrap it with electrical tape?

Thanks again

drz · 02-23-2010, 09:14 PM

Yup, literally sticking the golf tee up the end of the hose. Then, I'd recommend that you wrap it up well, maybe even use a wire tie, and some extra tape.