3.0TFSI faults P2279 & P0068

[roman_tyk]

Hi guys,

I am trying to figure out what is wrong with my C7 CGXB 3.0TFSI.
Car is working good, but i usually see some malfunctions in engine group:

6318 - Leak in Air Intake System
P2279 00 [109] - -
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 96495 km
Date: 2018.11.04
Time: 21:16:41

6307 - MAP/MAF <-> Throttle Position Correlation
P0068 00 [237] - -
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 96495 km
Date: 2018.11.04
Time: 21:16:41

6262 - Idle Control System RPM
P0507 00 [039] - Higher than Expected.
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 97269 km
Date: 2018.05.09
Time: 21:42:03

Sometimes Check Engine appears, then i feel some rough on idle rpms.
I changed spark plugs, change air filter to bosch. I check vacuum valve in rear view of engine. I don't hear any hiss from vacums.
I also performed throttle body adaptation (status OK).

Already checked:
1. throttle body cleaning and adaptation && replacement with another TB
2. checked evap valve (checked under 12V)
3. checked flap valve and SAI valves (checked under 12V)
4. checked SAI (its blowing air into engine)
5. checked vacum on valves in rear of engine (quite hard vacum on idle rpm)
6. new air filter (bosch) + engine oil
7. checked vacum lines (i don't hear potential leakage)
8. new spark plugs
9. PCV module (checked on idle that is possible to remove oil cap, just little vacum)
10. All fuses ok.
11. New PCV module "547AC"

Any ideas, what should i check?







Fault codes appears when car is warm/cold and when i am driving. When i stop the car, iddle rpm jumps to 1100rpm. I feel idle rough. Sometimes its jump from 900-1100.

[GilliamOS]

A quick Google returned these correlating possibilities.

Here and here

[roman_tyk]

i know description of those faults. I thought that someone had similar problems.
Till now i have been checked many things and haven't found rootcause:

- throttle body cleaning and adaptation
- checked evap valve,
- checked flap valve and SAI valves
- checked SAI
- checked vavum on valves
- new air filter
- checked vacum lines
- new spark plugs

next week i will exchange TB

[roman_tyk]

throttle body exchanged, still same errors.

Any ideas?

[dc2002]

Completely remove your intake piping and reinstall making sure all clamps are nice and tight and everything seated properly.

Was getting same error codes and did the above and that was my issue.

[roman_tyk]

Hi Dc2002,

you mean tube comming from airobox to throttle body? i reinstalled it several times during instalation of new air filter, exchanging throttle body.

Intake is really easy, we have just socket for SAI airbox and tube to TB.
Any possible leakage in intake is only possible between TB and supercharger (broken gasket).



Some interesting video from yt:
https://www.youtube.com/watch?v=U_MwYL5aa8Y

[dc2002]

Ok wasn't sure if you completely removed the intake piping or not. Maybe check for damage in the pipe and don't forget the small flex vacuum hose towards the back.

I had these exact codes when I installed my injen and something wasn't seated just right. Occasional CEL but would go away after a day or so.

EPL kept saying check your intake...and low and behold a year later and code free.

[roman_tyk]

EPL kept saying check your intake...and low and behold a year later and code free.

yes but please notice, the same code is used in different cars with MAF sensors, and in this case it's not obvious that issue is related to intake.
Many people have changed their intake to some custom, and they didn't notice any leakage.
Should any hole in airbox affect any disturbance in level of air comming to Throttle body?

I read several topics on forum, there are some issues which might be connected:
- dirty SAI valve in engine (carbon buildup in engine head secondary air ports) https://www.audizine.com/forum/showt...-3-0-TFSI-Pics!
- PCV problem. https://www.shopdap.com/blog/post/co...-engines1.html

On idle i feel only little vacum comming from this PCV line to tube before TB. Could somebody confirm that? Vacum comming to SAI electric valves is much more stronger.

[roman_tyk]

New PCV installed, problem solved. Now engine works perfectly, no issues on ECU.

[boostfix]

So nice when someone takes the time to circle back and post the actual fault! Right on!