Hi there, I have a stock 2008 Audi Q7. I was getting a P0171 & P0174 - 004 - System Too Lean - MIL ON. I replaced the PVC valve on it which means I removed the intake manifold and replaced the "cylinder head cover" which contains the PVC valve in it. As confirmation, I disassembled the old PVC assembly and looked at the diaphragm on the PVC. It had a large hole in it and the rubber was very brittle, so it definitely needed replacing. After reassembling and clearing the engine light, the car no longer throws the engine light or this error. I also replaced the fuel filter as a follow-up since I have owned this car for a while and have never replaced it. I wanted to just make sure that there was no fuel blockage issue contributing to the system lean error. Here's where the fun begins.
A few days after all these repairs, I'm feeling pretty good about my accomplishment. I'm driving on the highway and I put my foot into it pretty seriously to pass someone. The car Misfires and is running pretty rough with lack of power. I did a scan and found this.
I guess my thought is that the fuel injectors are bad, but before I address that, I wanted to get some input from the community experts. I guess it could also be some sort of lose connection in the wiring, but I've never seen this error code in the past. Hmmmm....
As a note, if I let the engine cool down and then restart it returns to normal. I can drive normally til the cows come home with no issues if I don't put my foot into the accelerator too hard. But what the heck! Why drive if you have that limitation?? Sometimes when I Push the accelerator hard, the engine light blinks a few times and things return back to normal if I back off on the accelerator quickly. If I clear the codes and take it out and do it again, it's not always the same cylinders which are misfiring. There may be a hint there....
Also, when I removed the intake manifold for the above maintenance, I had to remove the lower fuel rail to take it off. During reassembly, I replaced the old O-Rings on the fuel injectors. I didn't remove any of the electrical connectors from the fuel injectors. I also replaced all gaskets with new ones on the intake manifold and the Head cover during the original maintenance.
Lots of miles on this car. I have never replaced the injectors since I bought the car @ ~30K miles.
There is also an error code for the ABS brakes in the autoscan (also intermittent). Not sure what that's about.
Many thanks in advance for any suggestions or comments.
Paul
A few days after all these repairs, I'm feeling pretty good about my accomplishment. I'm driving on the highway and I put my foot into it pretty seriously to pass someone. The car Misfires and is running pretty rough with lack of power. I did a scan and found this.
Code:
Monday,28,September,2020,20:47:16:04546
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 20.4.2.0 (x64) HEX-V2 CB: 0.4513.4
Data version: 20200730 DS317.0
www.Ross-Tech.com
Dealer/Shop Name: Paul
VIN: WA1AY74L28D042453 License Plate:
Mileage: 249680km-155143mi Repair Order: 15
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Chassis Type: 4L (4L0)
Scan: 01 02 03 05 07 08 09 0E 0F 15 16 17 19 1E 42 46 47 4F 52 56
61 62 65 6D 6F 72
VIN: WA1AY74L28D042453 Mileage: 249680km-155143miles
00-Steering Angle Sensor -- Status: OK 0000
01-Engine -- Status: Malfunction 0010
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: Malfunction 0010
05-Acc/Start Auth. -- Status: OK 0000
07-Control Head -- Status: OK 0000
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
0E-Media Player 1 -- Status: OK 0000
0F-Digital Radio -- Status: Malfunction 0010
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
1E-Media Player 2 -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
46-Central Conv. -- Status: Malfunction 0010
47-Sound System -- Status: OK 0000
4F-Centr. Electr. II -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
56-Radio -- Status: OK 0000
61-Battery Regul. -- Status: Malfunction 0010
62-Door, Rear Left -- Status: OK 0000
65-Tire Pressure -- Status: OK 0000
6D-Trunk Elect. -- Status: OK 0000
6F-Centr. Conv. II -- Status: Malfunction 0010
72-Door, Rear Right -- Status: OK 0000
-------------------------------------------------------------------------------
Address 01: Engine (BHK) Labels: 03H-906-032-BLV.clb
Part No SW: 03H 906 032 CA HW: 03H 906 032 G
Component: Q7 3.6-FSI-LEV2 G 1379
Revision: 5CH05--- Serial number:
Coding: 0001175
Shop #: WSC 31414 790 00001
VCID: 6393A8C17754A4332F1-8036
6 Faults Found:
008518 - Supply Voltage for Fuel Injector Group A
P2146 - 002 - Open Circuit - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 249658 km
Time Indication: 0
Date: 2020.09.28
Time: 19:46:37
Freeze Frame:
RPM: 4107 /min
Load: 92.5 %
Speed: 80.0 km/h
Temperature: 88.0°C
Temperature: 24.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.589 V
000628 - Fuel Injector #5 (N83)
P0274 - 001 - Short to Plus - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 249658 km
Time Indication: 0
Date: 2020.09.28
Time: 19:46:37
Freeze Frame:
RPM: 4107 /min
Load: 92.5 %
Speed: 80.0 km/h
Temperature: 88.0°C
Temperature: 24.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.589 V
000768 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 - - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 249658 km
Time Indication: 0
Date: 2020.09.28
Time: 19:46:37
Freeze Frame:
RPM: 4230 /min
Load: 93.7 %
Speed: 81.0 km/h
Temperature: 88.0°C
Temperature: 24.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.716 V
000773 - Cylinder 5
P0305 - 001 - Misfire Detected - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 249658 km
Time Indication: 0
Date: 2020.09.28
Time: 19:46:37
Freeze Frame:
RPM: 4230 /min
Load: 93.7 %
Speed: 81.0 km/h
Temperature: 88.0°C
Temperature: 24.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.716 V
008518 - Supply Voltage for Fuel Injector Group A
P2146 - 002 - Open Circuit - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 249674 km
Time Indication: 0
Date: 2020.09.28
Time: 20:06:55
Freeze Frame:
RPM: 1475 /min
Load: 29.4 %
Speed: 64.0 km/h
Temperature: 88.0°C
Temperature: 26.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.716 V
000772 - Cylinder 4
P0304 - 001 - Misfire Detected - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 249675 km
Time Indication: 0
Date: 2020.09.28
Time: 20:08:41
Freeze Frame:
RPM: 1774 /min
Load: 52.5 %
Speed: 76.0 km/h
Temperature: 92.0°C
Temperature: 23.0°C
Absolute Pres.: 1000.0 mbar
Voltage: 13.589 V
Readiness: 0110 0100
-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 09E-927-156.lbl
Part No SW: 4L0 910 156 B HW: 0AT 927 156
Component: AG6 0AT 3,6 FSI USA 0010
Revision: --H04--- Serial number: 4035629
Coding: 0000002
Shop #: WSC 31414 790 00001
VCID: 2809FFED4EF2076B3A3-807C
No fault code found.
-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels:. 4L0-910-517-V2.clb
Part No SW: 4L0 910 517 B HW: 4L0 614 517 D
Component: ESP ALLRAD MK25E1 0010
Revision: 00H30001
Coding: 0099345
Shop #: WSC 31414 790 00001
VCID: 290FFAE955F83E6325D-807C
1 Fault Found:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
Freeze Frame:
Fault Status: 00101101
Fault Priority: 2
Fault Frequency: 1
Reset counter: 180
Mileage: 249620 km
Time Indication: 0
Date: 2020.09.26
Time: 15:28:02
Freeze Frame:
Count: 0
Count: 8257
Count: 8193
Count: 48640
-------------------------------------------------------------------------------
Address 05: Acc/Start Auth. Labels:. 4F0-910-852.clb
Part No SW: 4F0 910 852 HW: 4F0 905 852 B
Component: FBSAUDIC6 ELV H31 0230
Revision: 09010701 Serial number: 10601500957792
Coding: 0000131
Shop #: WSC 31414 790 00001
VCID: 6393A8C17754A4332F1-8036
Subsystem 1 - Part No: 4F0 910 131 J
Component: FBSAUDIC6 EZS H45 0080
Subsystem 2 - Part No: 4F0 910 220 A
Component: FBSAUDIC6 IDG H01 0040
No fault code found.
-------------------------------------------------------------------------------
Address 07: Control Head Labels: Redir Fail!
Part No SW: 4L0 910 730 Q HW: 4L0 035 730 C
Component: MMI Cockpit H80 0410
Revision: C61120EU Serial number: AUZ6Z2GBMD36I3
Coding: 0444222
Shop #: WSC 31414 790 00001
VCID: 3537269989406A83B15-8060
Subsystem 1 - Part No: 4F0 910 609 E
Component: Bedienteil MMIC6H01 0060
Subsystem 2 - Serial number: 00000001337903
Subsystem 3 - Serial number: 0123.06.090000000100010489ÿ
Subsystem 4 - Serial number: 010489ÿ
No fault code found.
-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: None
Part No SW: 4L0 910 043 B HW: 4L0 820 043 L
Component: KLIMABETAETIGUNGH07 0030
Revision: 00---013 Serial number: 00000030075150
Coding: 0524326
Shop #: WSC 31414 790 00001
VCID: 2313E8C137D4E4336F1-8076
No fault code found.
-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 4F0-910-279.lbl
Part No SW: 4F0 910 279 K HW: 4F0 907 279
Component: ILM Fahrer H18 0250
Revision: 00000000 Serial number: 4F0907279
Coding: 0010103
Shop #: WSC 31414 790 00001
VCID: 313F12897D2846A3EDD-8064
Subsystem 1 - Part No: 4L1 910 113 Labels: 1KX-955-119.CLB
Component: Wischer AU716 H14 0100
Coding: 00064792
Shop #: WSC 31414
Subsystem 2 - Part No: 4E0 910 557 B Labels: 8K0-955-559.CLB
Component: REGENLICHTSENSORH13 0100
Coding: 00150059
Shop #: WSC 31414
No fault code found.
-------------------------------------------------------------------------------
Address 0E: Media Player 1 Labels: None
Part No SW: 4L0 910 730 Q HW: 4L0 035 730 C
Component: MMI Cockpit H80 0410
Revision: C61120EU Serial number: AUZ6Z2GBMD36I3
Coding: 0444222
Shop #: WSC 31414 790 00001
VCID: 3537269989406A83B15-8060
No fault code found.
-------------------------------------------------------------------------------
Address 0F: Digital Radio Labels: 4E0-910-593-SIR.lbl
Part No SW: 4E0 910 593 K HW: 4E0 035 593 F
Component: SDAR SIRIUS H07 0140
Revision: 00000000 Serial number: AUZ4Z7G0215383
Coding: 0000100
Shop #: WSC 00000 000 00000
VCID: 2F3B14F16B1C5053FB9-807A
1 Fault Found:
02635 - Tuner Not Enabled/Activated
000 - -
Freeze Frame:
Fault Status: 01100000
Fault Priority: 7
Fault Frequency: 1
Reset counter: 255
Time Indication: 15
-------------------------------------------------------------------------------
Address 15: Airbags Labels: 4L0-910-655.lbl
Part No SW: 4L0 910 655 A HW: 4L0 959 655 B
Component: 73 AIRBAG AUDI8RH42 0230
Revision: 06H42000 Serial number: 0038QD07AHFD
Coding: 0014131
Shop #: WSC 31414 790 00001
VCID: 2B0300E15F042C73D71-807E
Subsystem 1 - Part No: 4L0 910 339 A
Component: BF-Gewichtsens. H03 0030
Subsystem 2 - Serial number: 6332QSME474D250BL
Subsystem 3 - Serial number: 6342QSME4B21413BD
Subsystem 4 - Serial number: 6352QSME45182D47L
Subsystem 5 - Serial number: 6362QSME506E3709M
Subsystem 6 - Serial number: 63734SME49611F3B8
Subsystem 7 - Serial number: 63834SME4B212911X
No fault code found.
-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 4F0-910-549.lbl
Part No SW: 4F0 910 549 A HW: 4F0 953 549 D
Component: J0527 0410
Revision: 00H03000 Serial number: 90055073260076
Coding: 0002022
Shop #: WSC 31414 790 00001
VCID: 270BFCD143EC0813339-8072
Subsystem 1 - Part No: XXXXXXXXXXX
Component: E0221 H02 0030
No fault code found.
-------------------------------------------------------------------------------
Address 17: Instruments Labels: 4L0-910-xxx-17.lbl
Part No SW: 4F0 910 900 C HW: 4L0 920 950 E
Component: KOMBIINSTR. M73 H16 0240
Revision: 00200000 Serial number: 65U11K4D7
Coding: 1555283
Shop #: WSC 01126 067 57207
VCID: 2019E7CD26C2FF2B723-8074
No fault code found.
-------------------------------------------------------------------------------
Address 19: CAN Gateway Labels:. 4L0-910-468.clb
Part No SW: 4L0 910 468 A HW: 4L0 907 468 B
Component: J533__Gateway H06 0060
Revision: 00H06000 Serial number: 1100B07B278015
Coding: E557BE57700A0200
Shop #: WSC 31414 790 00001
VCID: 2D070EF961102243C95-8078
No fault code found.
-------------------------------------------------------------------------------
Address 1E: Media Player 2 Labels: 4E0-910-111.lbl
Part No SW: 4L0 910 110 A HW: 4L0 035 110
Component: MP3-Changer H45 0350
Revision: 00045007 Serial number: AUZ5ZBG1242540
Shop #: WSC 00000 000 00000
VCID: 1D67DE3911B0D2C3595-8048
No fault code found.
-------------------------------------------------------------------------------
Address 42: Door Elect, Driver Labels: 4L0-910-793-42.lbl
Part No SW: 4L0 910 793 B HW: 4L0 959 793 B
Component: TSG FA H12 0150
Revision: 00-00000
Coding: 0035403
Shop #: WSC 31414 790 00001
VCID: 2F3B14F16B1C5053FB9-807A
No fault code found.
-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 4L0-910-289.lbl
Part No SW: 4L0 910 289 F HW: 4L0 907 289 C
Component: Komfortgeraet H07 0050
Revision: 0050 --- Serial number: 01084767680000
Coding: 7370781
Shop #: WSC 31414 790 00001
VCID: 33331881873474B39F1-8066
Subsystem 1 - Part No: 1K0 951 605 C
Component: LIN BACKUP HORN H03 1301
1 Fault Found:
01403 - Glass-Break Sensors; Rear
011 - Open Circuit
Freeze Frame:
Fault Status: 01101011
Fault Priority: 3
Fault Frequency: 254
Reset counter: 143
Mileage: 0 km
Time Indication: 0
-------------------------------------------------------------------------------
Address 47: Sound System (J525) Labels: Redir Fail!
Part No SW: 4L0 910 223 H HW: 4L0 035 223 C
Component: DSP-AU716-RD H07 0250
Revision: S0900000
Coding: 060000
Shop #: WSC 31414 790 00001
VCID: 290FFAE959F83E6325D-807C
No fault code found.
-------------------------------------------------------------------------------
Address 4F: Centr. Electr. II Labels: 4F0-910-280.lbl
Part No SW: 4F0 910 280 HW: 4F0 907 280 D
Component: ILM Beifahrer H12 0100
Revision: Serial number: 00000000022253
Coding: 0012001
Shop #: WSC 31414 790 00001
VCID: 5EE599355C3689DB00F-800A
No fault code found.
-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. Labels: 4L0-910-793-52.lbl
Part No SW: 4L0 910 793 B HW: 4L0 959 792 B
Component: TSG BF H12 0150
Revision: 00-00000
Coding: 0035403
Shop #: WSC 31414 790 00001
VCID: 2F3B14F16B1C5053FB9-807A
No fault code found.
-------------------------------------------------------------------------------
Address 56: Radio Labels: None
Part No SW: 4L0 910 730 Q HW: 4L0 035 730 C
Component: MMI Cockpit H80 0410
Revision: C61120EU Serial number: AUZ6Z2GBMD36I3
Coding: 0444222
Shop #: WSC 31414 790 00001
VCID: 3537269989406A83B15-8060
No fault code found.
-------------------------------------------------------------------------------
Address 61: Battery Regul. Labels: 4F0-910-181.lbl
Part No SW: 4L0 910 181 A HW: 4L0 915 181
Component: J0644 BEM H12 0690
Revision: -------- Serial number: 00000000043063
Shop #: WSC 07109 444 57830
VCID: 2517F6D939E01A03015-8070
Subsystem 1 - Part No: 4F0 915 105 C
Component: von VA0 2711240739
Coding: 344630393135313035432056413032373131323430373339
Shop #: WSC 31414 790 00001
1 Fault Found:
02256 - Quiescent Current
001 - Upper Limit Exceeded - Intermittent
Freeze Frame:
Fault Status: 00100001
Fault Priority: 7
Fault Frequency: 4
Reset counter: 171
Mileage: 249179 km
Time Indication: 0
Date: 2020.09.05
Time: 22:08:11
-------------------------------------------------------------------------------
Address 62: Door, Rear Left Labels: 4L0-910-795.lbl
Part No SW: 4L0 910 795 B HW: 4L0 959 795 B
Component: TSG HL H21 0150
Coding: 0035338
Shop #: WSC 31414 790 00001
VCID: 313F12897D2846A3EDD-8064
No fault code found.
-------------------------------------------------------------------------------
Address 65: Tire Pressure Labels: 4F0-910-273-BA.lbl
Part No SW: 4F0 910 273 B HW: 4F0 907 273 A
Component: Reifendruck 3 H05 0100
Revision: 00050100 Serial number: 00000900061728
Coding: 0062424
Shop #: WSC 31414 790 00001
VCID: 221DEDC528CEED3B647-8076
No fault code found.
-------------------------------------------------------------------------------
Address 6D: Trunk Elect. Labels: 4L0-910-945.clb
Part No SW: 4L0 910 945 HW: 4L0 827 851 C
Component: ValeoHeckdeckel H25 0290
Revision: --H25001 Serial number: E5030000B
Shop #: WSC 98765 666 38354
VCID: 6C81C3FD9A8AEB4B9EB-8038
Subsystem 1 - Part No: 4L0 910 946
Component: ValeoHeckdeckel H25 0290
Subsystem 2 - Serial number: E5030100B
Subsystem 3 - Serial number: RD07.12.07--H25001001B0054ÿ
Subsystem 4 - Serial number: 1B0054ÿ
No fault code found.
-------------------------------------------------------------------------------
Address 6F: Centr. Conv. II Labels:. 4L0-910-290.lbl
Part No SW: 4L0 910 290 A HW: 4L0 907 290 A
Component: ILM HINTEN 2 H05 0060
Revision: AAH05061 Serial number: 003314871-----
Coding: 0000009
Shop #: WSC 31414 790 00001
VCID: 2615F1D544E6111B08F-8072
1 Fault Found:
02961 - Lamp in Bumper; Rear Right
009 - Open or Short to Ground
Freeze Frame:
Fault Status: 01101001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 97
Mileage: 248545 km
Time Indication: 0
Date: 2020.07.12
Time: 12:50:32
Freeze Frame:
Bin. Bits: 000 100
-------------------------------------------------------------------------------
Address 72: Door, Rear Right Labels: 4L0-910-795.lbl
Part No SW: 4L0 910 795 B HW: 4L0 959 794 B
Component: TSG HR H21 0150
Coding: 0035338
Shop #: WSC 31414 790 00001
VCID: 313F12897D2846A3EDD-8064
No fault code found.
End----------(Elapsed Time: 01:43, VBatt start/end: 14.0V/13.9V)-----------
I guess my thought is that the fuel injectors are bad, but before I address that, I wanted to get some input from the community experts. I guess it could also be some sort of lose connection in the wiring, but I've never seen this error code in the past. Hmmmm....
As a note, if I let the engine cool down and then restart it returns to normal. I can drive normally til the cows come home with no issues if I don't put my foot into the accelerator too hard. But what the heck! Why drive if you have that limitation?? Sometimes when I Push the accelerator hard, the engine light blinks a few times and things return back to normal if I back off on the accelerator quickly. If I clear the codes and take it out and do it again, it's not always the same cylinders which are misfiring. There may be a hint there....
Also, when I removed the intake manifold for the above maintenance, I had to remove the lower fuel rail to take it off. During reassembly, I replaced the old O-Rings on the fuel injectors. I didn't remove any of the electrical connectors from the fuel injectors. I also replaced all gaskets with new ones on the intake manifold and the Head cover during the original maintenance.
Lots of miles on this car. I have never replaced the injectors since I bought the car @ ~30K miles.
There is also an error code for the ABS brakes in the autoscan (also intermittent). Not sure what that's about.
Many thanks in advance for any suggestions or comments.
Paul