Q5 Carbon on exhaust tips
 

Does anybody have advice for removing the carbon build-up on the chrome exhaust tips on a 2014 2.0T? I hand wash the car several time a week and when it was new the carbon came off very easy. Now at 4,100 miles it no longer wipes off with a towl or sponge and is getting harder to remove. Any tips?

I sprayed on WD40 and wiped off with a rag. No more carbon build up. Any carbon residue will wash off easily.

Perhaps a good metal polish? I use Zainx and I could be spelling that wrong as I'm going from memory (it's cold in the garage!).

I've used NeverDull - in a blue can - in the past with very good results. It's a chemically treated cotton that doesn't scratch.

Get a TDI ;) I haven't seen any carbon yet...At least not near as much as on my 2.0t

After 14 months I don't have any build up on the tips. I wonder what would make the difference? Gas type? We're 10% ethanol around here.

I'm pretty sure we are 10% ethanol as well. What octane gasoline are you using. My dealer told me when I bought the car to run 89 octane. I questioned him since the owners manual says to run premium fuel. He explained that premium fuel in Germany is 89 octane.

I alternate between mid-grade (89 octane) and premium (91).

AS Q5TDI has posted, Try Neverdull. You can find it at most auto parts stores. It's cotton matting won't scratch, and leaves the surface a little oily so the buildup won't come back as fast.

I think your dealer is dyslexic. Premium fuel in Germany is actually 98 RON, which equals 93 AKI (the octane scale we use in NA). Regardless, octane has nothing to do with tailpipe soot. Soot is most likely a function of the DI fuel delivery and DI engines typically run very rich on cold starts. If your driving pattern is typically lots of shorter trips with fewer long ones there'll be more soot. Also, any oil consumption will contribute to fouled tips.

I've owned four vehicles with DI, and the only one that didn't have a lot of tailpipe soot was an F150 which was 90% highway driven.