2.0 TFSI P0171 partial

[Pacht]

Hello fellow Audi-drivers

I have issues with my 2.0 tfsi (ea888, CCZZA). Currently 130tkm, new engine at 108tkm.

I got in dezember 2020 a new vacuum pump, unfortunately they used silicon to seal it.

March 2021 I hade issues under heavy load and some fault codes. Car was running too rich so I changed the fuel pressure sensor for a new Bosch one. That didn't help so I went to Audi dealer for fixing, since I had a used car warranty.

They changed the injectors and the high pressure pump.

After that, I noticed that my adaption was going wild:
-1 ~ -3% idle
+16 ~ 18% partial

So I changed a lot, because I don't think brand new injectors are broken.

- Connector tube Turbo-Inlet (was ripped, didn't help tho=
- MAF (Hitachi)
- 1st O2 Sensor (Bosch)
- OEM PCV (made it even worse)
- spark plugs (all old ones seem fine and no difference)
- intercooler for Golf 6 R
- K&N filter (no change)

I checked already a couple of times for vacuum leaks with high pressure. Also, what I could reach I sucked on to check the vacuum.
N80 seems to work fine.
N75 was missing some clamps, didn't help tho.

I'm running out of ideas what to check for.
Rear main seal i doubt, because the engine is new and the PCV was not really broken, tho I have small oil somewhere. Wouldn't i notice it with pressure anyways?

Currently at:
-1~-3% idle
+27% partial, so MIL ON

Thanks for ideas.

[Pacht]

Nobody any idea?

[Silicon Voodoo]

If you have lean issues because of a vacuum leak, you may have a ripped brake booster. Normally diagnostic requires a smoke test no? If you can't do that, try changing the tube from the pump to the intake manifold. The breather hoses, the PCV tubes, and dismount your PCV valve again, re-seal it with some sort of grease. Try to listen to the diagnostic pin-hole on the valve too. Check your valve cover gasket for leaks, or cracks.

[Pacht]

Thanks. I have a ea888, not ea113.