2008 Q7 4.2 TDI V8 Limp mode on hard acceleration after engine warms up

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
Chassis Type: 4L (4L0)
Scan: 01 02 03 05 07 08 09 0E 11 31 15 16 17 18 19 1E 28 34 36 37
42 46 47 4F 52 55 56 57 61 62 69 6C 6D 6F 72 76 77

VIN: WAUZZZ4L98D063928 Mileage: 183640km-114108miles

00-Steering Angle Sensor -- Status: OK 0000
01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
05-Acc/Start Auth. -- Status: Malfunction 0010
07-Control Head -- Status: Malfunction 0010
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
0E-Media Player 1 -- Status: Malfunction 0010
11-Engine II -- Status: OK 0000
31-Engine other -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
18-Aux. Heat -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
1E-Media Player 2 -- Status: OK 0000
28-HVAC, Rear -- Status: OK 0000
34-Level Control -- Status: OK 0000
36-Seat Mem. Drvr -- Status: OK 0000
37-Navigation -- Status: OK 0000
42-Door Elect, Driver -- Status: Malfunction 0010
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
55-Headlight Range -- Status: OK 0000
56-Radio -- Status: OK 0000
57-TV Tuner -- Status: Malfunction 0010
61-Battery Regul. -- Status: OK 0000
62-Door, Rear Left -- Status: OK 0000
69-Trailer -- Status: OK 0000
6C-Back-up Cam. -- Status: Malfunction 0010
6D-Trunk Elect. -- Status: OK 0000
6F-Centr. Conv. II -- Status: OK 0000
72-Door, Rear Right -- Status: Malfunction 0010
76-Park Assist -- Status: OK 0000
77-Telephone -- Status: OK 0000
-------------------------------------------------------------------------------
Address 01: Engine Labels: Redir Fail!
Part No SW: 4L0 910 409 D HW: 4E1 907 409 B
Component: 4.2L V8TDI G001AGMª0010
Revision: --H10--- Serial number:
Coding: 0011779
Shop #: WSC 55579 001 1048576
VCID: 2B0303C82F005F33D71-807E

No fault code found.
Readiness: 0 0 0 X 0

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 09D-927-750.clb
Part No SW: 09D 927 750 JJ HW: 09D 927 750 JJ
Component: AL 750 6A 1167
Revision: 00H78000 Serial number:
Coding: 0000504
Shop #: WSC 31414 790 00001
VCID: 7F5B07988BF813932B9-802A

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: 0103601
Shop #: WSC 31414 790 00001
VCID: 290FF9C025FC4D2325D-807C

No fault code found.

-------------------------------------------------------------------------------
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: 10601501028958
Coding: 0000151
Shop #: WSC 30372 000 1048576
VCID: 6393ABE80750D7732F1-8036

Subsystem 1 - Part No: 4F0 910 131 C
Component: FBSAUDIC6 EZS H46 0080

Subsystem 2 - Part No: 4F0 910 335
Component: FBSAUDIC6 KSG H27 0080

Subsystem 3 - Part No: 4F0 910 220 F
Component: FBSAUDIC6 IDG H01 0060

3 Faults Found:
00190 - Driver's Door Handle Touch Sensor (G415)
007 - Short to Ground
Freeze Frame:
Fault Status: 01110111
Fault Priority: 3
Fault Frequency: 1
Reset counter: 18
Time Indication: 0

00191 - Passenger's Door Handle Touch Sensor (G416)
007 - Short to Ground
Freeze Frame:
Fault Status: 01110111
Fault Priority: 3
Fault Frequency: 1
Reset counter: 18
Time Indication: 0

00193 - Rear Right Door Handle Touch Sensor (G418)
007 - Short to Ground
Freeze Frame:
Fault Status: 01110111
Fault Priority: 3
Fault Frequency: 1
Reset counter: 18
Time Indication: 0


-------------------------------------------------------------------------------
Address 07: Control Head Labels: 4L0-910-7xx-07-H.clb
Part No SW: 4L0 910 732 G HW: 4E0 035 729 A
Component: Interfacebox H43 5140
Revision: 00000000 Serial number: 387DW087571703
Coding: 0002002
Shop #: WSC 31414 790 00001
VCID: 2D070DD011145103C95-8078

Subsystem 1 - Part No: 4L0 910 609
Component: E0380 BedienteilH01 0060

Subsystem 2 - Serial number: 00000001042018

Subsystem 3 - Serial number: 0103.04.080000000100011610ÿ

Subsystem 4 - Serial number: 011610ÿ

1 Fault Found:
01325 - Control Module for Tire Pressure Monitoring (J502)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 5
Fault Frequency: 1
Reset counter: 18
Mileage: 183280 km
Time Indication: 0
Date: 2020.10.15
Time: 08:01:09


-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: None
Part No SW: 4L0 910 043 B HW: 4L0 820 043 M
Component: KLIMABETAETIGUNGH07 0040
Revision: 00---015 Serial number: 00000000261746
Coding: 0132184
Shop #: WSC 20460 822 86671
VCID: 2313EBE847D097736F1-8076

No fault code found.

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 4F0-910-279.lbl
Part No SW: 4F0 910 279 J HW: 4F0 907 279 A
Component: ILM Fahrer H18 0250
Revision: 00000000 Serial number: 4F0907279
Coding: 0113121
Shop #: WSC 31414 790 00001
VCID: 303914A406263CEBE23-8064

Subsystem 1 - Part No: 4L2 910 113 Labels: 1KX-955-119.CLB
Component: Wischer AU716 H11 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: 4E0-910-111.lbl
Part No SW: 4L0 910 110 B HW: 4L0 035 110
Component: MP3-Changer H45 0390
Revision: 00045002 Serial number: AUZ5ZBH8378675
Shop #: WSC 00000 000 00000
VCID: 1E65DA1C6CB2BA9B40F-804A

1 Fault Found:
02446 - Disk Drive Mechanical Malfunction
014 - Defective
Freeze Frame:
Fault Status: 01101110
Fault Priority: 7
Fault Frequency: 2
Reset counter: 67
Mileage: 183255 km
Time Indication: 0
Date: 2020.10.14
Time: 14:00:23


-------------------------------------------------------------------------------
Address 11: Engine II Labels: Redir Fail!
Part No SW: 4L0 910 409 D HW: 4E1 907 409 B
Component: 4.2L V8TDI G001AGSª0010
Revision: --H10--- Serial number:
Coding: 0011779
Shop #: WSC 55579 001 1048576
VCID: 2B0303C82F005F33D71-807E

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 4L0-910-655.lbl
Part No SW: 4L0 910 655 D HW: 4L0 959 655 C
Component: 70 AIRBAG AUDI8RH42 0230
Revision: 03H42000 Serial number: 00399D04DYNM
Coding: 0014128
Shop #: WSC 31414 790 00001
VCID: 2E050ADC1C122A1BF0F-807A

Subsystem 1 - Serial number: 6332QSME5D6C2645S

Subsystem 2 - Serial number: 6342QSME5C793661P

Subsystem 3 - Serial number: 6352QSME5C6F146B.

Subsystem 4 - Serial number: 6362QSME5C061875M

Subsystem 5 - Serial number: 63734SME5A7751676

Subsystem 6 - Serial number: 63834SME31400B40P

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: 90026080920117
Coding: 0112142
Shop #: WSC 31414 790 00001
VCID: 270BFFF833E87B53339-8072

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 910 930 C HW: 4L0 920 930 T
Component: KOMBIINSTR. M73 H23 0240
Revision: 00000000 Serial number: 73Y153948
Coding: 2593702
Shop #: WSC 12345 067 57207
VCID: 2313EBE847D097736F1-8076

No fault code found.

-------------------------------------------------------------------------------
Address 18: Aux. Heat Labels: 4L0-910-105.lbl
Part No SW: 4L0 910 105 HW: 4L0 815 071 E
Component: Heizgeraet H08 0090
Revision: 0000000D Serial number: 00000009014264
Coding: 0000001
Shop #: WSC 31414 790 00001
VCID: 6099A4E41646CC6B323-8034

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: 1100B0840580B0
Coding: F7FBFEFF70360200
Shop #: WSC 14124 002 1048576
VCID: 2D070DD011145103C95-8078

No fault code found.

-------------------------------------------------------------------------------
Address 1E: Media Player 2 (R199) Labels:. 4E0-035-785.lbl
Part No SW: 4E0 035 785 F HW: 4E0 035 785 C
Component: SG ext.Player H20 0850
Revision: 00000000
Coding: 010000
Shop #: WSC 00000 000 00000
VCID: 2B0303C823005F33D71-807E

No fault code found.

-------------------------------------------------------------------------------
Address 28: HVAC, Rear Labels: None
Part No SW: 4L0 910 158 HW: 4L0 919 158 C
Component: KLIMABETAETIGUNGH05 0060
Revision: 00---009 Serial number: 00000030088522
Coding: 0000006
Shop #: WSC 31414 790 00001
VCID: 6889BCC4FE76B42BFA3-803C

No fault code found.

-------------------------------------------------------------------------------
Address 34: Level Control Labels: 4L0-910-553.lbl
Part No SW: 4L0 910 553 C HW: 4L0 907 553
Component: LUFTFDR.-CDC H03 7660
Revision: --H03001 Serial number: 15.1528-0096.2
Coding: 0015520
Shop #: WSC 48312 000 1048576
VCID: 2A0D06CC20FA463B2C7-807E

No fault code found.

-------------------------------------------------------------------------------
Address 36: Seat Mem. Drvr Labels: None
Part No SW: 4F0 910 760 HW: 4L0 959 760
Component: Sitzmemory FS H01 0100
Revision: 00000000 Serial number: 00000000896401
Coding: 0091146
Shop #: WSC 31414 790 00001
VCID: 619FA1E01D4CC5633DD-8034

No fault code found.

-------------------------------------------------------------------------------
Address 37: Navigation Labels: 4E0-910-88x-37.lbl
Part No SW: 4E0 910 888 E HW: 4E0 919 887 M
Component: MNS ECE H51 1050
Revision: 00000000 Serial number: 399D.087612574
Shop #: WSC 22080 822 86671
VCID: 303914A406263CEBE23-8064

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: 00000000 Serial number: Vb
Coding: 0017051
Shop #: WSC 31414 790 00001
VCID: 2F3B17D81B182313FB9-807A

2 Faults Found:
02123 - Door Warning Light / Entry Light
012 - Electrical Fault in Circuit
Freeze Frame:
Fault Status: 01101100
Fault Priority: 3
Fault Frequency: 9
Reset counter: 67
Mileage: 183253 km
Time Indication: 0
Date: 2020.10.14
Time: 13:51:56

02126 - Central Locking Button; Exterior Door Handle
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 3
Fault Frequency: 93
Reset counter: 67
Mileage: 183253 km
Time Indication: 0
Date: 2020.10.14
Time: 13:51:56


-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 4L0-910-289.lbl
Part No SW: 4L0 910 289 F HW: 4L0 907 289 C
Component: Komfortgeraet H08 0060
Revision: 0060 --- Serial number: 01102252300000
Coding: 7602317
Shop #: WSC 22080 822 86671
VCID: 33331BA8F73007F39F1-8066

1 Fault Found:
03073 - Rear Lid Closed Sensor 1
008 - Implausible Signal - Intermittent
Freeze Frame:
Fault Status: 00101000
Fault Priority: 5
Fault Frequency: 18
Reset counter: 105
Mileage: 183499 km
Time Indication: 0
Date: 2020.11.01
Time: 07:13:41


-------------------------------------------------------------------------------
Address 47: Sound System Labels: 4L0-910-223-BO.lbl
Part No SW: 4L0 910 223 G HW: 4L0 035 223 D
Component: DSP-High AU716 H03 0150
Revision: PROD_01 Serial number: 00000000063068
Coding: 0000013
Shop #: WSC 31414 790 00001
VCID: 2809FCC43EF6742B3A3-807C

No fault code found.

-------------------------------------------------------------------------------
Address 4F: Centr. Electr. II Labels: 4F0-910-280.lbl
Part No SW: 4F0 910 280 HW: 4F0 907 280
Component: ILM Beifahrer H12 0100
Revision: Serial number: 00000000355333
Coding: 0011001
Shop #: WSC 31414 790 00001
VCID: 5EE59A1C2C32FA9B00F-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: 0017051
Shop #: WSC 31414 790 00001
VCID: 2F3B17D81B182313FB9-807A

No fault code found.

-------------------------------------------------------------------------------
Address 55: Headlight Range Labels: 4F0-910-357.lbl
Part No SW: 4L0 910 357 HW: 4L0 907 357
Component: AFS 1 H01 0040
Revision: 00000001 Serial number:
Coding: 0000022
Shop #: WSC 31414 790 00001
VCID: 698FB9C0E57C8D23E5D-803C

Subsystem 1 - Part No: 7L6 941 329 A
Component: AFS-Modul links H07 0004

Subsystem 2 - Part No: 7L6 941 329 A
Component: AFS-Modul rechtsH07 0004

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 4E0-910-541.lbl
Part No SW: 4E0 910 541 Q HW: 4E0 035 541 S
Component: TUNER EU/US/RDW H42 0620
Revision: 00000000 Serial number: 388D-087683522
Coding: 0000001
Shop #: WSC 31414 790 00001
VCID: 2E050ADC1C122A1BF0F-807A

No fault code found.

-------------------------------------------------------------------------------
Address 57: TV Tuner Labels: None
Part No SW: 4E0 910 148 D HW: 4E0 919 148
Component: R78 TVHybridDVB 0440
Revision: R0H06000 Serial number: 76300801377301
Coding: 0000307
Shop #: WSC 31414 790 00001
VCID: 2411E8F442DE904B16B-8070

1 Fault Found:
02283 - Video Connection to Output [End Unit]
010 - Open or Short to Plus - Intermittent
Freeze Frame:
Fault Status: 00101010
Fault Priority: 5
Fault Frequency: 1
Reset counter: 79
Mileage: 183471 km
Time Indication: 0
Date: 2020.10.30
Time: 07:13:30


-------------------------------------------------------------------------------
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: 00000000016768
Shop #: WSC 22080 822 86671
VCID: 2517F5F049E46943015-8070

Subsystem 1 - Part No: 000 915 105 DL
Component: von VA0 330607701Z
Coding: 303030393135313035444C5641303333303630373730315A
Shop #: WSC 59719 001 104857

No fault code found.

-------------------------------------------------------------------------------
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: 0016386
Shop #: WSC 31414 790 00001
VCID: 313F11A00D2C35E3EDD-8064

No fault code found.

-------------------------------------------------------------------------------
Address 69: Trailer Labels: 4E0-910-383.lbl
Part No SW: 4E0 910 383 C HW: 4E0 907 383 C
Component: ANHAENGERELEKTR 004 0060
Coding: 0000002
Shop #: WSC 31414 790 00001
VCID: 2411E8F442DE904B16B-8070

No fault code found.

-------------------------------------------------------------------------------
Address 6C: Back-up Cam. Labels: 4L0-910-441.clb
Part No SW: 4L0 910 441 A HW: 4L0 907 441 A
Component: J772__Rearview 0050
Revision: --H12--- Serial number: 525PA8-J8341HY
Coding: 1031001
Shop #: WSC 31414 790 00001
VCID: 2411E8F442DE904B16B-8070

1 Fault Found:
03006 - Back-up Camera System not calibrated
000 - -
Freeze Frame:
Fault Status: 01100000
Fault Priority: 2
Fault Frequency: 1
Reset counter: 18
Time Indication: 0

Freeze Frame:
Invalid
Invalid
Invalid


-------------------------------------------------------------------------------
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: 6C81C0D4EA8E980B9EB-8038

Subsystem 1 - Part No: 4L0 910 946
Component: ValeoHeckdeckel H25 0290

Subsystem 2 - Serial number: E5030100B

Subsystem 3 - Serial number: RD14.04.08--H25001001B0185ÿ

Subsystem 4 - Serial number: 1B0185ÿ

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: 003602080-----
Coding: 0003843
Shop #: WSC 22080 822 86671
VCID: 2615F2FC34E2625B08F-8072

Subsystem 1 - Part No: 4L0 910 591
Component: J_245_EE16_SKB09H10 0200

Subsystem 2 - Part No: 4L0 910 591
Component: J_394_EE16_SKB09H10 0200

Subsystem 3 - Part No: 4L0 910 591
Component: J_392_EE16_SKB09H10 0200

No fault code found.

-------------------------------------------------------------------------------
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: 0016386
Shop #: WSC 31414 790 00001
VCID: 313F11A00D2C35E3EDD-8064

1 Fault Found:
02126 - Central Locking Button; Exterior Door Handle
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 3
Fault Frequency: 1
Reset counter: 18
Mileage: 183253 km
Time Indication: 0
Date: 2020.10.14
Time: 13:52:04


-------------------------------------------------------------------------------
Address 76: Park Assist Labels: 4Fx-910-283.lbl
Part No SW: 4F0 910 283 K HW: 4F0 919 283 K
Component: Parkhilfe 8-Kan H12 0100
Revision: 00H12000 Serial number: 69820809303808
Coding: 0231146
Shop #: WSC 31414 790 00001
VCID: 2C0100D42A0E580BDEB-8078

No fault code found.

-------------------------------------------------------------------------------
Address 77: Telephone Labels: 4E0-910-336.lbl
Part No SW: 4E0 910 336 M HW: 4E0 862 335
Component: Handyvorb2 H16 1130
Revision: 00000000 Serial number: 00000007589562
Coding: 0010920
Shop #: WSC 20460 822 173925
VCID: 2C0100D42A0E580BDEB-8078

No fault code found.

End----------(Elapsed Time: 02:30, VBatt start/end: 13.4V/13.7V)-----------
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
Thanks, will do.

I did graph measuring block 022 which I understand to be fuel pressure. The green line will be specified pressure and the yellow will be actual. You can see the yellow (actual) was consistent with the green (specified) until about half way along the time line. That is where I put the accelerator down and the engine went into limp mode.

Now I am not sure whether the yellow (actual) pressure falls away because the engine went into limp mode and the ECU said I don't need fuel or whether the drop in (actual) fuel pressure actually caused the limp mode.

I would suspect the later because the green line (specified pressure) does not drop but stays constant for a short period. Although, I am not sure why it would be so flat - at that point the specified fuel pressure is reading about 1650 bar given that the max vertical scale is set at 2000 bar.

Anyone know if this is normal?

 

tdi_my live

Veteran Member
Joined
Jul 24, 2011
Location
Germany
TDI
Skoda Fabia
That's a good question. I think you would have to log several blocks at the same time. For example 8-11-22 together. Maybe there is a discrepancy in the boost pressure.
Can you post the log available as a csv original format. I would like to see it in Excel.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
Thanks, I will try your suggestion tomorrow. After I switched the car off, the car would not start again. Almost like it had fuel vapour lock. I know that is rare for a diesel. Started again after it cooled down.
 

tdi_my live

Veteran Member
Joined
Jul 24, 2011
Location
Germany
TDI
Skoda Fabia
That will be a temperature problem. Either water, oil or exhaust gas is so high that the car will not start for safety reasons.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
That will be a temperature problem. Either water, oil or exhaust gas is so high that the car will not start for safety reasons.
Thanks, I see if I can check temperatures on the VCDS. I may well be wrong but I wonder whether the CATs are blocked causing a back pressure issue (or exhaust gas temperature issue) that the ECU reacts to but there is no DTC because of the DPF delete and those systems no longer being measured.

Is there a way to measure exhaust gas temperature when those DPF measuring systems have been blocked?
 

tdi_my live

Veteran Member
Joined
Jul 24, 2011
Location
Germany
TDI
Skoda Fabia
Don't get confused by the fact that you don't have any DTC entries. If the tuner has snapped them all away, nothing ever comes, although there is a problem. You need the flasher for a read out. Than is all clear to see.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
I am still waiting on the flasher. It throws a MAF dtc when I disconnect the MAFs. You can drive with no limp mode when the MAFs are disconnected but I suspect that will be because the car is running on default safe air and fuel values and in no way working under such loads/extremes.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
I have been told to flash the ECUs back to stock in order to be able to get dtcs but if you think it is better to get the flasher and read the software then I will do that.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
I have been using the VCDS to measure the torque 008; turbo pressure 011 and fuel pressure 022 blocks within Engine - 01 controller. Not yet finished but I am curious whether anyone can assist with what the field values within MVB 008 actually are?

In MVB 008 field 1 is engine speed in rpm; at idle field 2 measures 161.7nm; field 3 is 415.8nm and field 4 is 383.5nm.

When I run the car and graph this MVB, field 2 will rise under acceleration and peak at about 850nm and plateau and fields 3 and 4 will follow similar paths with each other and usually peak slightly lower or at the same value as field 2.

Just trying to work out what I am looking at? I assume field 2 plateaus due to a torque limiter.

Also, I note there is a MVB 009 which at idle reads: field 1 is (-110.9nm); field 2 is 947.1nm; field 3 is (-231.0nm) and field 4 is 947.1nm. Does anyone know what these torque values relate to?

Thanks
 

tdi_my live

Veteran Member
Joined
Jul 24, 2011
Location
Germany
TDI
Skoda Fabia
08 is:
1. speed, rpm
2. Accelerator pedal torque, Nm
3. Torque, Nm
4. Smoke limiter, Nm

09 is:
1. speed, rpm
2. Speed torque, Nm
3. Gear torque, Nm
4. Limiting torque, Nm; so what triggers the limitation

You use vcds?
You can save the log, and look in excel about the converter
 

Hayze

Member
Joined
May 30, 2020
Location
Oklahoma City
TDI
2009 Jetta
The limp mode is quite dramatic as car can still be driven but has very limited throttle response and sound of engine changes as if the timing is then retarded.

Car has DPF delete with stage 1 tune to ECU. No error codes being thrown.

Have cleaned the MAFs and disconnected the MAF sensors and it appears the engine then uses a set of default air flow values. The check engine light comes on and the engine performance appears restricted.

People often talk of overboost causing limp mode. From what I can tell overboost does not throw error codes?

I understand this car has VNT turbos with actuators that are controlled by electric cable from ECU?

I also don't understand why the engine will pull great without issue until the engine reaches operating temperature. Does the ECU in some sort of safety measure limit boost or fuel until the engine reaches operating temperature and that is why we only possibly get issue when operating temperature is reached?

First i will state that i have a Cold air intake on my TDI.
I just leave the MAF sensor unplugged, and only plug it in when the car says dpf filter is full and needs regen.

2nd. You say car has dpf delete with stage 1 tune. Did you delete the EGR? Did you delete the NOX canister from underneath the car? Did you delete the Exhaust flapper valve? (If you have one)

Also need to consider that Tuning can have some risks in it self, if all is well and the parts mentioned above for delete dont need to be deleted.
My guess could be that its a faulty tune, since your not getting any actual codes.

3rd. Yes limp mode is very Very "VERY" dramatic when it activates. But as i mentioned earlier, depending on the issue that has limp mode activated.
You can leave your MAF unplugged most cases and it drive better than it actually being plugged in.

This may not be an overboost related issue, unless someone has actually messed with the VNT actuator bolts and the veins are now out of alignment which can cause an overboost issue since the boost pressure is outside (higher than normal) of ECM's boost parameters.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
First i will state that i have a Cold air intake on my TDI.
I just leave the MAF sensor unplugged, and only plug it in when the car says dpf filter is full and needs regen.

2nd. You say car has dpf delete with stage 1 tune. Did you delete the EGR? Did you delete the NOX canister from underneath the car? Did you delete the Exhaust flapper valve? (If you have one)

Also need to consider that Tuning can have some risks in it self, if all is well and the parts mentioned above for delete dont need to be deleted.
My guess could be that its a faulty tune, since your not getting any actual codes.

3rd. Yes limp mode is very Very "VERY" dramatic when it activates. But as i mentioned earlier, depending on the issue that has limp mode activated.
You can leave your MAF unplugged most cases and it drive better than it actually being plugged in.

This may not be an overboost related issue, unless someone has actually messed with the VNT actuator bolts and the veins are now out of alignment which can cause an overboost issue since the boost pressure is outside (higher than normal) of ECM's boost parameters.
The NOx canisters are still there. No exhaust flapper that I am aware of exists on this car. It is not my tune but that of prior owner. I can see the EGRs are still there on the engine but I have been told the EGR valves have been deactivated but not blanked off.

When the MAFS are disconnected the performance suffers as the ECU is running on some set of safe air/fuel values but no limp mode.

Could be bad tune but speaking with previous owners this is the 3rd tune from different tuners where the limp mode persists on all tunes. So there is an underlying problem.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
08 is:
1. speed, rpm
2. Accelerator pedal torque, Nm
3. Torque, Nm
4. Smoke limiter, Nm

09 is:
1. speed, rpm
2. Speed torque, Nm
3. Gear torque, Nm
4. Limiting torque, Nm; so what triggers the limitation

You use vcds?
You can save the log, and look in excel about the converter
I did use the VCDS but I am still trying to work out how to save the log. Will investigate further tomorrow and do some more runs. It is still limp mode only after operating temperature is reached and only if I hold the accelerator down for an extended period of time. If I hit the accelerator hard but pull back quickly then no limp mode. But I guess it makes sense that the problematic parameter has to go out of spec for an extended period before the ECU shuts the engine into safe mode.

I note MVB 009 provides limiting torque as 947.1nm but when I graph the engine running, maximum torque is plateauing at only about 830-840nm?

Thanks
 

tdi_my live

Veteran Member
Joined
Jul 24, 2011
Location
Germany
TDI
Skoda Fabia
At 947.1 Nm there would be a limit if the other values are programmed higher. I would focus on 08.
Even here, it is not easy to make statements about the actual injection quantity. We need logs 01-08-011 for example.

I think the button is called record. Then give the file a name. Then you can start and stop the recording.
 

Big Lebowski

Active member
Joined
Oct 1, 2020
Location
Australia
TDI
Audi 4.2 TDI
I have been using the VCDS to measure the torque 008; turbo pressure 011 and fuel pressure 022 blocks within Engine - 01 controller. Not yet finished but I am curious whether anyone can assist with what the field values within MVB 008 actually are?

In MVB 008 field 1 is engine speed in rpm; at idle field 2 measures 161.7nm; field 3 is 415.8nm and field 4 is 383.5nm.

When I run the car and graph this MVB, field 2 will rise under acceleration and peak at about 850nm and plateau and fields 3 and 4 will follow similar paths with each other and usually peak slightly lower or at the same value as field 2.

Just trying to work out what I am looking at? I assume field 2 plateaus due to a torque limiter.

Also, I note there is a MVB 009 which at idle reads: field 1 is (-110.9nm); field 2 is 947.1nm; field 3 is (-231.0nm) and field 4 is 947.1nm. Does anyone know what these torque values relate to?

Thanks
 
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