I have a 328i with the sport package and so it has a nice metal twin tailpipe coming out the back. Whenever I wash the car, I notice that it has some black spots on it which are either cooked road tar and/or stains from the exhaust itself (on the lips). I've tried getting these spots off with bug and tar remover but this doesn't work and since I don't know what it's made of, I've been reluctant to try anything "stronger" (ie: metal polish, etc.). Does anyone have an idea what I can try in order to clean this black stuff off without damaging the metal surface of the tailpipe?
I noticed the same thing with my 328. It's just exhaust sediment, but it does kind of bake on. I first tried wadding polish, no good. I just got some Smartpolish by Smartwax this week and it worked well. I needed a little elbow grease but it cut the sooty stuff without scratching. My poor old pickup is the guinea pig for any car care product before it gets to my car.
I use this - gives you an awesome cleaning effect without too much elbow grease - make your exhaust look like new. http://www.mothers.com/02_products/05106.html
The new turbo 4 bangers are really spittin out some crude for some reason. Mine are black and nothing will get it off. Brass cleaner, chrome cleaner, WD-40, nothing. Have heard you can take steel wool to it but I don't know the type so I haven't gone that route yet.
Tar remover then a piece of clay bar that you don't plan on using on paint ever again works pretty well.
Go to ACE hardware, get a package of "bronze wool", hit the "wool" with Dawn and add elbow grease. Should do the job..if not take it up a notch with Mothers Meatal Cleaner and Wool. Rinse wool out when done and save for next use. Apply some carnuba to outside and inside of tips...makes it easier next time.
