2014 2L TFSI Idle fault

[Adam Watson]

Hi

I have an Audi A4 Avant 2L TFSI Quattro - CDNC engine and its developed a fault causing a terrible idle and EML light.

Scanned with VCDS and there are 7 faults in the engine:

                Address 01: Engine       Labels: 06H-907-115-CDN.clb
Control Module Part Number: 8K5 907 115 H    HW: 8K2 907 115 L
  Component and/or Version: 2.0l R4/4V TF H09 0004
           Software Coding: 12250013244601022000
            Work Shop Code: WSC 38633 001 1048576
              ASAM Dataset: EV_ECM20TFS0118K5907115H 001006 (AU48)
                       ROD: EV_ECM20TFS0118K5907115H.rod
                      VCID: 372B2BC12FCE7A62FE1-8062
7 Faults Found:

5646 - 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: 89159 km
                    Date: 2024.11.11
                    Time: 20:20:33

                    Engine RPM: 1082.50 /min
                    Normed load value: 7.1 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 86 °C
                    Intake air temperature: 25 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 14.465 V
                    Unlearning counter according OBD: 40
                    Mean injection time: 1.390 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5
                    Driver-side belt buckle status-Bits 0-7: 77
                    Engine torque: 14.1 Nm

4007 - Idle Control System RPM
          P0507 00 [032] - Higher than Expected.
          Intermittent - Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 89159 km
                    Date: 2024.11.11
                    Time: 20:20:32

                    Engine RPM: 1166.50 /min
                    Normed load value: 6.3 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 92 °C
                    Intake air temperature: 45 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 13.169 V
                    Unlearning counter according OBD: 37
                    Mean injection time: 1.344 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5
                    Driver-side belt buckle status-Bits 0-7: 32
                    Engine torque: 13.0 Nm

10203 - Random/Multiple Cylinder Misfire Detected
          P0300 00 [039] - -
          Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 89200 km
                    Date: 2024.11.12
                    Time: 17:37:26

                    Engine RPM: 730.00 /min
                    Normed load value: 10.2 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 67 °C
                    Intake air temperature: 41 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 14.041 V
                    Unlearning counter according OBD: 80
                    Mean injection time: 1.571 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5

10593 - Cylinder 3
          P0303 00 [039] - Misfire Detected
          Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 89200 km
                    Date: 2024.11.12
                    Time: 17:38:46

                    Engine RPM: 727.50 /min
                    Normed load value: 10.6 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 75 °C
                    Intake air temperature: 37 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 14.300 V
                    Unlearning counter according OBD: 80
                    Mean injection time: 1.626 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5

10594 - Cylinder 4
          P0304 00 [039] - Misfire Detected
          Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 89200 km
                    Date: 2024.11.12
                    Time: 17:37:26

                    Engine RPM: 706.00 /min
                    Normed load value: 10.2 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 67 °C
                    Intake air temperature: 41 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 14.112 V
                    Unlearning counter according OBD: 80
                    Mean injection time: 1.598 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5

10592 - Cylinder 2
          P0302 00 [039] - Misfire Detected
          Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 89200 km
                    Date: 2024.11.12
                    Time: 17:37:26

                    Engine RPM: 730.00 /min
                    Normed load value: 10.2 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 67 °C
                    Intake air temperature: 41 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 14.041 V
                    Unlearning counter according OBD: 80
                    Mean injection time: 1.571 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5

4105 - Bank 1; System too Lean at Idle
          P2187 00 [237] - -
          MIL ON - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 89187 km
                    Date: 2024.11.12
                    Time: 15:31:18

                    Engine RPM: 848.50 /min
                    Normed load value: 8.2 %
                    Vehicle speed: 1 km/h
                    Coolant temperature: 90 °C
                    Intake air temperature: 36 °C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 14.229 V
                    Unlearning counter according OBD: 40
                    Mean injection time: 1.559 ms
                    Engine operating condition: Idle
                    Engine operating condition-Test_Program_Channel 87: 5
                    Driver-side belt buckle status-Bits 0-7: 112
                    Engine torque: 20.8 Nm

Seems its obviously a an air leak somewhere? Had a look around all the hoses I can see for anything obvious but couldn't see anything. The idle is really rough but revs seemingly cleanly enough.

Any tips to aid diagnosis would be great

Thanks
Adam

[Crasher]

Disconnect the cam cover breather vent hose from the inlet manifold and allow it to breath to atmosphere, externally cap (there is a strong vacuum) the port on the inlet manifold. If this stops the poor running, fit a new breather unit. If this is left a long time it cam damage the crank front and rear seals plus suck in the chain cover gasket.

[Adam Watson]

Thanks Crasher, will give it a go

[Adam Watson]

followed the instructions, pointed to the PCV, replaced that and all is well again. Many thanks