minmet

The other day I was wiping the tail pipe and noticed the inside is getting dark. My finger wipe tells a thin layer of black soot. I have just 5k miles after 4 months with moderate driving. RPM hasn't exceeded 4000 yet and oil level is still at full mark. And then, this morning, I walked pass a same car in our work place garage. I did a quick finger wipe to the tail pipe and there is a thick layer of black coke.
This A4 is my first turbocharged car. Are all turbos has the soot or vw/audi 2.0t particularly susceptible to soot. I did notice that lots of BMW 3s have unsightly blackened tail pipes. I thought only diesel cars have black tail pipes.

VipinLJ

Diesel cars smoke like no other. But yes. Looks like our petrols produce soot too. Mine has the same thing though not much since it has done only 2200 miles.

redherring

My old 2010 A4 2.0T crapped up the pipes so badly that after a while the chrome couldn't be cleaned anymore and I had to replace the tips, but my 2013 Q5 (with the same motor) has been much better. 2017 A4 so far has been clean as a whistle but only 3,000 mi. so probably too soon to tell.

snagitseven

It's not soot - it's carbon deposits. All direct injected engines exhibit this to one degree or another.

minmet

Both my old Honda Pilot and Toyota Camry had no any hint of soot in the tail piper after 10 years and >100k miles. My current Lexus RX350 and Honda Pilot which is direct injected also have no any hint of soot after two years and >20k miles each. Guess I will need to change my mind set now.
Probably just an Backyard Shadetree mechanics' unnecessary worry.

minmet

If this is carbon build up and we see it in the tail pipe, aren't carbon deposits building up on the valves and inside the chamber? A quick search found that VW/Audi 2.0t to some extent the Audi V6 are indeed most susceptible to carbon deposits among all the direct injected engines. And yes, more so in the direct injected than in natural aspired engines.

Michael Karesh, the developer of TrueDelta.com said “The only engines it’s reported quite a bit is [with] the VW/Audi 2.0T and then the Audi V6s.” He also said, “I know there are some BMWs that end up with carbon buildup as well.”

I bought the car and plan to hold long. Looks I will have to be proactive dealing this issue.

KevinB656

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tjones78

Yes, pretty common. It seems that Coke and steel wool is a great solution for cleaning it.

A4Driver

My A4 is 11 months old with only 6,000 miles on the clock. Just this past week I noticed a slight hint of carbon buildup on the tailpipes, which is amazing because by '09 A4 would blacken the pipes in one week. I was constantly using chrome cleaner to try to remove the carbon, but it became a losing battle.

Also pretty amazing is that my oil level hasn't gone down at all, whereas my '09 (before the oil-related recall) was using a quart every 1,200 miles.
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minmet

Encouraging. Looks VW/Audi improved already compare to older models.