rok2774
01-01-2024, 05:10 AM
2014 Audi A4 quattro 2.0 - 129,000 miles. Car drives flawlessly.
Been chasing a CEL for a few months - P2177 (System too lean off idle) and periodically P0177 (Fuel Composition Sensor Circuit Range/Performance). I am not seeing any loss in MPG or major hesitation while starting up or driving.
When the CEL is on the LTFT stays around positive 5-8%. After clearing the codes the LTFT shoots to positive 30-35% and the car hesitates for 2 seconds then returns to a smooth idle. After 1 or 2 drives the CEL will return every time but car drives and accelerates just fine otherwise.
Searched the end of the internet and back and have tried the following:
1. New MAF sensor
2. New upstream O2 sensor
3. New OEM plugs and coils
4. New OEM latest-rev PCV
5. Checked for vacuum leak with smoke test
6. Ran fuel injector cleaner (Berryman B12) through multiple tanks of gas
I am leaning toward possibly the injectors being clogged or the HPFP failing.... I may replace the HPFP and fuel sensor (I read these should be proactively replaced around 100K any way) to see if it resolves.
Is there anything else I could/should be looking at? I don't have VAGCOM but i can run reports using another OBD2 app if someone lets me know which items to track.
Thanks!
Been chasing a CEL for a few months - P2177 (System too lean off idle) and periodically P0177 (Fuel Composition Sensor Circuit Range/Performance). I am not seeing any loss in MPG or major hesitation while starting up or driving.
When the CEL is on the LTFT stays around positive 5-8%. After clearing the codes the LTFT shoots to positive 30-35% and the car hesitates for 2 seconds then returns to a smooth idle. After 1 or 2 drives the CEL will return every time but car drives and accelerates just fine otherwise.
Searched the end of the internet and back and have tried the following:
1. New MAF sensor
2. New upstream O2 sensor
3. New OEM plugs and coils
4. New OEM latest-rev PCV
5. Checked for vacuum leak with smoke test
6. Ran fuel injector cleaner (Berryman B12) through multiple tanks of gas
I am leaning toward possibly the injectors being clogged or the HPFP failing.... I may replace the HPFP and fuel sensor (I read these should be proactively replaced around 100K any way) to see if it resolves.
Is there anything else I could/should be looking at? I don't have VAGCOM but i can run reports using another OBD2 app if someone lets me know which items to track.
Thanks!