Running rich? Carbon buildup?

[Rajini98]

Lately, I've noticed a smell coming from the exhaust that makes it smell like I'm running catless when I have the OEM downpipe. In addition to that, my exhaust is covered in black soot even after cleaning it just over 100 miles ago.

Looking around, this sounds like it could be running too rich and/or a failing cat. I thought that failing cats rattled or something. To top all this off, the car doesn't immediately turn over like it used to. When it runs though, it sounds fine and my gas mileage is unchanged.

I did recently have PCV issues that were resolved where I was blowing giant clouds of smoke out the exhaust under boost so I could have an intake full of oil deposits. Maybe I just need to clean the intake valves

Spark plugs and air filter were changed less than 5k ago, oil changed less than 500 miles ago.

Does anyone have any more advice for things I could look into?

 

[Mrvdub444]

What about your cam follower and thrust sensor? When was the last time those where changed? I've noticed my problem is the same as yours. Try those two solutions then let's us know.

Thrust sensor aka low pressure fuel sensor

 

[Mrvdub444]

Also, I just order a new cam follower and thrust sensor

 

[NJdubber]

thrust sensor wont cause black soot, it will throw codese, fuel cuts or low pressure readings. I would log the car and see how the car is running to confirm what's up. Normally these cars do cause the tips to go black due to the nature of the Direct Injection FSI technology.

 

[Rajini98]

Guess I should have mentioned that I did the cam follower about 2 months ago. I'm not throwing any codes or misfiring either. I'll see what I can do as far as logs go. What should I log?

I have a pretty strong feeling that it's carbon buildup from the PCV failure throwing stuff off. It's an air restriction post MAP sensor which could throw off A/F ratio. 70k+ miles and havent cleaned it yet.

Maybe I have a fouled O2 sensor too from the same problem.

EDIT:
I did some measurements with my phone at idle.
My A:F is 14.7 to 1