R36 BWS, random high idle RPM, system lean

[jerr]

As title suggests, the car is randomly at about 1100 RPM at a stop for a few secs, then goes back to 7-800 RPM.

I have looked at RossTech however would be great if any owner can shed some lights, as I am not sure whether this is a Low Pressure/High pressure fuel sensor issue or a rear main seal issue(which is leaking a bit but not horrible)

I have used VCDS and returned these logs for engine:

Address 01: Engine (BWS) Labels: 03H-906-032-BLV.clb
Part No SW: 03H 906 032 FS HW: 03H 906 032 AB
Component: CC3.6-FSI-EU5 G 4855


4 Faults Found:
004506 - Fuel Pressure Sensor (G247)
P119A - 001 - Malfunction - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 8
Reset counter: 255
Mileage: 114311 km
Time Indication: 0
Date: 2018.03.17
Time: 09:41:57


Freeze Frame:
RPM: 650 /min
Load: 16.5 %
Speed: 0.0 km/h
Temperature: 65.0 C
Temperature: 42.0 C
Absolute Pres.: 1000.0 mbar
Voltage: 14.097 V


001287 - Idle Control System RPM
P0507 - 001 - Higher than Expected. - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 3
Reset counter: 255
Mileage: 114323 km
Time Indication: 0
Date: 2018.03.17
Time: 11:57:21


Freeze Frame:
RPM: 1016 /min
Load: 16.9 %
Speed: 0.0 km/h
Temperature: 85.0 C
Temperature: 39.0 C
Absolute Pres.: 1010.0 mbar
Voltage: 13.843 V


000372 - Fuel Trim; Bank 2
P0174 - 004 - System Too Lean - Intermittent
Freeze Frame:
Fault Status: 00100100
Fault Priority: 0
Fault Frequency: 2
Reset counter: 255
Mileage: 114403 km
Time Indication: 0
Date: 2018.03.17
Time: 00:06:46


Freeze Frame:
RPM: 643 /min
Load: 17.2 %
Speed: 0.0 km/h
Temperature: 85.0 C
Temperature: 26.0 C
Absolute Pres.: 1000.0 mbar
Voltage: 13.970 V


000369 - Fuel Trim; Bank 1
P0171 - 004 - System Too Lean - Intermittent
Freeze Frame:
Fault Status: 00100100
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 114403 km
Time Indication: 0
Date: 2018.03.17
Time: 00:06:49


Freeze Frame:
RPM: 644 /min
Load: 17.2 %
Speed: 0.0 km/h
Temperature: 85.0 C
Temperature: 26.0 C
Absolute Pres.: 1000.0 mbar
Voltage: 13.843 V

[Lucas_R]

A hunting idle is usually an air leak somewhere. Check all your vacuum lines going to the intake as well as your airbox etc. Also the PCV's on the 3.2 and 3.6L V6's are very well known for leaking - so this is likely to be a possibility.

RKX 3.6 3.2 L Valve Cover PCV Valve Diaphragm membrane for VW AUDI 3.6L VR6 R32 | eBay