2007 Audi Q7 3.0 TDI - Crank No Fire

   #1  

ClisbyAutoElectrical

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Hi there, we currently have a 2007 Audi Q7 3.0 TDI in at our workshop. It has come in after the customer has had the issue
where, they were driving at 100KM/H up a hill and the glow plug light started flashing, and from what the customer said
the vehicle then went into limp mode - Only would go about 40KM/H. So only having the glow plug light to
go on, the customer decided to change all of the glow plugs with a cheap eBay variant. In the process of changing the glow-
plugs, the customer removed the common rail off of the engine to gain better access.

After the customer had refitted the glow plugs and the common rail, the vehicle would not start. Upon not starting the
customer got roadside assist to come out to see if they could do anything. They scanned the vehicle and it returned these codes
from the ECU:

00565 Turbo/super charger boost sensor A Circ. - Sporadic
001 - Upper limit exceeded

01025 Exhaust gas recirc. Flow insufficient detected - Sporadic
002 - Lower limit exceeded

04501 Fuel pressure regulator valve. Open circuit/short circuit to ground
Sporadic 001 - Upper limit exceeded

Of course the roadside assistant cleared all of the codes so there was no freeze frame data to go on. So with the information that
I had to go on (did not know at this point the common rail had been taken off at this point), I started with the basics, checked all
fuses and fuseable links, ensured nothing was missing from any of the fuse boxes. I checked there was power getting to terminal 30 of
the fuel pump relay, and the glow plug relay both were getting battery voltage. At this point I decided to get genuine glow plugs and fit them,
just to eliminate the eBay plugs causing any issues. Which obviously has not magically resolved the issue haha, but i figured it was worth a try.

So when scanning the vehicle now there are no fault codes present in the ECU, and codes that are in any other of the vehicles modules aren't really
giving me anything to go on. So I had to start further diagnosis, i checked for current draw on the glow plugs under ignition and cranking conditions,
Neither time did i get any current draw, although this could be possible due to a high ambient temp. If i perform an output test to the glow plug circuit
i will get current draw, so the circuit is working. At this point i rang the customer once again to confirm what work had been done to the vehicle
This is when they told me they had taken the common rail off to do the glow plugs, they also stated that if they sprayed some starting solvent into
the vehicles intake they could get it to run for a short period of time.

So now armed with that information i start looking for a fueling issue, i performed a current draw test on the injectors under cranking conditions, and there
zero current draw, i also checked the fuel metering valve with an output test and it was operating correctly. I ran the in tank fuel pump for about 3 to 5 mins
by bridging out the relay, i did this to ensure sufficient fuel pressure was getting to the fuel filter and high pressure fuel pump, as well as cranking the vehicle
and checked the fuel line for any air bubbles. To be 100% sure the tank pump was working i pulled the supply hose off the inlet of the high pressure pump, and diesel was flowing fine.

Due to the fact the glow plugs aren't operating at all, and neither are the injectors it seems to me like either a basic setting or an immobilizer issue has come into play.
Either that or I'm missing something obvious haha. Hopefully someone might be able to give something, to go on or just be able to bounce ideas around.

Thanks heaps! Sorry of I've missed anything this is my first time posting on here.


Code:
Thursday,05,March,2020,15:56:19:36219
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 19.6.2.2 (x64)  HEX-V2 CB: 0.4508.4
Data version: 20200210 DS308.0
www.Ross-Tech.com

Dealer/Shop Name: Clisby Auto Electrical

VIN: WAUZZZ4L47D100253   License Plate: 


Chassis Type: 4L (4L0)
Scan: 01 02 03 05 07 08 09 0E 15 16 17 18 19 1E 37 42 46 47 4F 52
          56 61 62 67 6C 6D 6F 72 76 77

VIN: WAUZZZ4L47D100253   Mileage: 200910km-124839miles

00-Steering Angle Sensor -- Status: OK 0000
01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: Malfunction 0010
05-Acc/Start Auth. -- Status: OK 0000
07-Control Head -- Status: Malfunction 0010
08-Auto HVAC -- Status: Malfunction 0010
09-Cent. Elect. -- Status: OK 0000
0E-Media Player 1 -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
18-Aux. Heat -- Status: Malfunction 0010
19-CAN Gateway -- Status: Malfunction 0010
1E-Media Player 2 -- Status: OK 0000
37-Navigation -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
46-Central Conv. -- Status: OK 0000
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
67-Voice Control -- Status: OK 0000
6C-Back-up Cam. -- Status: Malfunction 0010
6D-Trunk Elect. -- Status: OK 0000
6F-Centr. Conv. II -- Status: Malfunction 0010
72-Door, Rear Right -- Status: OK 0000
76-Park Assist -- Status: OK 0000
77-Telephone -- Status: Cannot be reached 1100
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 059-907-401-ASB.clb
   Part No SW: 4L0 910 401 M    HW: 4L0 907 401 
   Component: 3.0L V6TDI  G000AG  0030  
   Revision: --H04---    Serial number:               
   Coding: 0011779
   Shop #: WSC 80093 222 69422
   VCID: 2C0105436A03E0D745D-8078

No fault code found.
Readiness: 0 0 1 1 1 

-------------------------------------------------------------------------------
Address 02: Auto Trans        Labels: 09D-927-750.clb
   Part No SW: 09D 927 750 FS    HW: 09D 927 750 FS
   Component: AL 750 6A           1000  
   Revision: 00H64000    Serial number:               
   Coding: 0000504
   Shop #: WSC 31414 790 00001
   VCID: 04518DE3A213C897EDD-8050

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels:. 4L0-910-517-V1.clb
   Part No SW: 4L0 910 517 A    HW: 4L0 614 517 A
   Component: ESP ALLRAD MK25E1   0130  
   Revision: 00H22001    
   Coding: 0033937
   Shop #: WSC 31414 790 00001
   VCID: 2809F9537EFBCCF7A15-807C

2 Faults Found:
00668 - Supply Voltage Terminal 30 
            002 - Lower Limit Exceeded - Intermittent
             Freeze Frame:
                    Fault Status: 00100010
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 98
                    Mileage: 200913 km
                    Time Indication: 0
                    Date: 2020.03.02
                    Time: 15:58:45

             Freeze Frame:
                    Count: 0
                    Count: 6149
                    Count: 128
                    Count: 31232

01826 - Sensor for Steering Angle (G85); Supply Voltage Terminal 30 
            000 - -
             Freeze Frame:
                    Fault Status: 01100000
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 98
                    Mileage: 200913 km
                    Time Indication: 0
                    Date: 2020.03.02
                    Time: 15:56:33

             Freeze Frame:
                    Count: 0
                    Count: 4357
                    Count: 297
                    Count: 40704


-------------------------------------------------------------------------------
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 0220  
   Revision: 31050601    Serial number: 10601100724493
   Coding: 0000147
   Shop #: WSC 31414 790 00001
   VCID: 6393AE7F475D6FAFB47-8036

   Subsystem 1 - Part No: 4F0 910 131 A
   Component: FBSAUDIC6 EZS   H45 0080

   Subsystem 2 - Part No: 4F0 910 220 
   Component: FBSAUDIC6 IDG   H01 0040

No fault code found.

-------------------------------------------------------------------------------
Address 07: Control Head        Labels: 4L0-910-7xx-07-H.clb
   Part No SW: 4L0 910 731 D    HW: 4E0 035 729 A
   Component: Interfacebox    H43 3450  
   Revision: 00000000    Serial number: 387DV077543533
   Coding: 0002002
   Shop #: WSC 31414 790 00001
   VCID: 290FFC5765F1F5FFBEB-807C

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

   Subsystem 2 - Serial number: 00000000717268

   Subsystem 3 - Serial number: 0129.03.070000000100010417ÿ

   Subsystem 4 - Serial number: 010417ÿ

1 Fault Found:
00003 - Control Module 
            005 - No or Incorrect Basic Setting / Adaptation
             Freeze Frame:
                    Fault Status: 01100101
                    Fault Priority: 5
                    Fault Frequency: 1
                    Reset counter: 98
                    Mileage: 200913 km
                    Time Indication: 0
                    Date: 2020.03.04
                    Time: 13:04:06


-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: None
   Part No SW: 4L0 910 043     HW: 4L0 820 043 E
   Component: KLIMABETAETIGUNGH05 0060  
   Revision: 00---012    Serial number: 00000000109888
   Coding: 0001110
   Shop #: WSC 31414 790 00001
   VCID: 619FA4775D417DBFA6B-8034

1 Fault Found:
00446 - Function Limitation due to Under-Voltage 
            000 - - - Intermittent
             Freeze Frame:
                    Fault Status: 00100000
                    Fault Priority: 6
                    Fault Frequency: 2
                    Reset counter: 138
                    Mileage: 200912 km
                    Time Indication: 0
                    Date: 2006.11.23
                    Time: 12:06:59

             Freeze Frame:
                    Voltage: 10.00 V


-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels: 4F0-910-279.lbl
   Part No SW: 4F0 910 279 K    HW: 4F0 907 279 
   Component: ILM Fahrer      H17 0240  
   Revision: 00000000    Serial number: 4F0907279     
   Coding: 0000101
   Shop #: WSC 31414 790 00001
   VCID: 313F14374D218D3F76B-8064

   Subsystem 1 - Part No: 4L2 910 113   Labels: 1KX-955-119.CLB
   Component: Wischer AU716   H08 0080  
   Coding: 00064792
   Shop #: WSC 31414  

   Subsystem 2 - Part No: 4E0 910 557 A  Labels: 8K0-955-559.CLB
   Component: REGENLICHTSENSORH13 0090  
   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 A    HW: 4L0 035 110 
   Component: MP3-Changer     H43 0350  
   Revision: 00043000    Serial number: AUZ5ZBG1042885
   Shop #: WSC 00000 000 00000
   VCID: 1D67D88721B9195FC23-8048

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 4L0-910-655.lbl
   Part No SW: 4L0 910 655 B    HW: 4L0 959 655 
   Component: 30 AIRBAG AUDI8RH39 0120  
   Revision: 06H39000    Serial number: 0037GD09AFPC  
   Coding: 0013104
   Shop #: WSC 31414 790 00001
   VCID: 2C0105436A03E0D745D-8078

   Subsystem 1 - Serial number: 6332QSME26763543B

   Subsystem 2 - Serial number: 6342QSME254C0F4FX

   Subsystem 3 - Serial number: 6352QSME240D15114

   Subsystem 4 - Serial number: 6362QSME27023767C

   Subsystem 5 - Serial number: 63734SME25572225V

   Subsystem 6 - Serial number: 63834SME25570C392

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 4F0-910-549.lbl
   Part No SW: 4F0 910 549     HW: 4F0 953 549 A
   Component: Lenksäulenmodul H08 0230  
   Revision: 00H08000    Serial number: 90026070850006
   Coding: 0102142
   Shop #: WSC 31414 790 00001
   VCID: 6695B76BB46F1A87539-8032

   Subsystem 1 - Part No: XXXXXXXXXXX 
   Component: Lenkradmodul    H07 0090

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 4L0-910-xxx-17.lbl
   Part No SW: 4F0 910 930 C    HW: 4L0 920 930 H
   Component: KOMBIINSTR. M73 H18 0170  
   Revision: 00400000    Serial number: 5HG56C947     
   Coding: 2561748
   Shop #: WSC 04577 067 57207
   VCID: 2313EE7F07DD2FAFF47-8076

No fault code found.

-------------------------------------------------------------------------------
Address 18: Aux. Heat        Labels: 4L0-910-105.lbl
   Part No SW: 4L0 910 105     HW: 4L0 815 071 D
   Component: Heizgeraet      H08 0080  
   Revision: 0000000C    Serial number: 00000009014264
   Coding: 0000001
   Shop #: WSC 31414 790 00001
   VCID: 6099A173564B74B7A95-8034

1 Fault Found:
01413 - Dosing/Metering Pump (V54) 
            007 - Short to Ground

-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels:. 4L0-910-468.clb
   Part No SW: 4L0 910 468     HW: 4L0 907 468 
   Component: J533__Gateway   H06 0040  
   Revision: 00H06000    Serial number: 0900B0733083F9
   Coding: F55BFE57707202
   Shop #: WSC 22080 822 86671
   VCID: 6C81C543AA8320D705D-8038

1 Fault Found:
01303 - Telephone Transceiver (R36) 
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 3
                    Fault Frequency: 1
                    Reset counter: 98
                    Mileage: 200913 km
                    Time Indication: 0
                    Date: 2020.03.04
                    Time: 13:05:07


-------------------------------------------------------------------------------
Address 1E: Media Player 2 (R192)       Labels:. 4E0-035-785.lbl
   Part No SW: 4E0 035 785     HW: 4E0 035 785 
   Component: SG ext.Player H09 0170  
   Revision: 00000000    
   VCID: 6597B0674569119F5A3-8030

No fault code found.

-------------------------------------------------------------------------------
Address 37: Navigation        Labels: 4E0-910-88x-37.lbl
   Part No SW: 4E0 910 888 J    HW: 4E0 919 887 M
   Component: MNS ECE         H49 1040  
   Revision: 00000000    Serial number: 364D.077676258
   Shop #: WSC 22080 822 86671
   VCID: 35372027B949A11F2A3-8060

No fault code found.

-------------------------------------------------------------------------------
Address 42: Door Elect, Driver        Labels: 4L0-910-793-42.lbl
   Part No SW: 4L0 910 793 C    HW: 4L0 959 793 C
   Component: TSG FA          H21 0050  
   Coding: 0000539
   Shop #: WSC 31414 790 00001
   VCID: 30391133462B8437795-8064

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 0040  
   Revision: 0040 ---    Serial number: 01038157280000
   Coding: 7602309
   Shop #: WSC 31850 812 66137
   VCID: 33331E3FB73DBF2F047-8066

No fault code found.

-------------------------------------------------------------------------------
Address 47: Sound System (J525)       Labels: Redir Fail!
   Part No SW: 4L0 910 223 E    HW: 4L0 035 223 C
   Component: DSP-AU716-RD  H07 0130  
   Revision: 05S00000    
   Coding: 030100
   Shop #: WSC 31414 790 00001
   VCID: 2615F76B78EFDA87939-8072

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   H10 0080  
   Revision:             Serial number: 00000000245721
   Coding: 0011001
   Shop #: WSC 31414 790 00001
   VCID: 5EE59F8B6C3F42479B9-800A

No fault code found.

-------------------------------------------------------------------------------
Address 52: Door Elect, Pass.        Labels: 4L0-910-793-52.lbl
   Part No SW: 4L0 910 792 C    HW: 4L0 959 792 C
   Component: TSG BF          H21 0050  
   Coding: 0000539
   Shop #: WSC 31414 790 00001
   VCID: 2F3B124F5B159BCF60F-807A

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: 388C-077615844
   Coding: 0000001
   Shop #: WSC 31414 790 00001
   VCID: 2E050F4B5C1F92C76B9-807A

No fault code found.

-------------------------------------------------------------------------------
Address 61: Battery Regul.        Labels: 4F0-910-181.lbl
   Part No SW: 4L0 910 181     HW: 4L0 915 181 
   Component: J0644 BEM       H12 0530  
   Revision: --------    Serial number: 00000000016769
   Shop #: WSC 31850 812 66137
   VCID: 6491AD63425368974DD-8030

   Subsystem 1 - Part No: 4F0 915 105 D
   Component: von VA0  340327R0W2       
   Coding: 344630393135313035442056413033343033323752305732
   Shop #: WSC 60589 001 1048576

2 Faults Found:
02256 - Quiescent Current 
            001 - Upper Limit Exceeded - Intermittent
             Freeze Frame:
                    Fault Status: 00100001
                    Fault Priority: 7
                    Fault Frequency: 2
                    Reset counter: 138
                    Mileage: 200913 km
                    Time Indication: 0
                    Date: 2020.03.04
                    Time: 23:30:48

03041 - Energy Management Active 
            000 - - - Intermittent
             Freeze Frame:
                    Fault Status: 00100000
                    Fault Priority: 7
                    Fault Frequency: 1
                    Reset counter: 255
                    Mileage: 200912 km
                    Time Indication: 0
                    Date: 2006.11.23
                    Time: 13:23:29


-------------------------------------------------------------------------------
Address 62: Door, Rear Left        Labels: 4L0-910-795.lbl
   Part No SW: 4L0 910 795 C    HW: 4L0 959 795 C
   Component: TSG HL          H21 0050  
   Coding: 0000002
   Shop #: WSC 31414 790 00001
   VCID: 323D1B3B4827B6270F1-8066

No fault code found.

-------------------------------------------------------------------------------
Address 67: Voice Control        Labels: 4E0-910-75x-67.lbl
   Part No SW: 4E0 910 754 S    HW: 4E0 035 753 A
   Component: SDS 3502 UK     H45 0630  
   Revision: 00000000    Serial number: 00000703090411
   Shop #: WSC 12336 024 394758
   VCID: 3635272BA44FAA07239-8062

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-J7340KA
   Coding: 1021101
   Shop #: WSC 31414 790 00001
   VCID: 2411ED6302D328978DD-8070

1 Fault Found:
00778 - Steering Angle Sensor (G85) 
            013 - Check DTC Memory
             Freeze Frame:
                    Fault Status: 01101101
                    Fault Priority: 3
                    Fault Frequency: 1
                    Reset counter: 98
                    Mileage: 200912 km
                    Time Indication: 0
                    Date: 2006.11.23
                    Time: 17:37:32

             Freeze Frame:
                        Term 15 On
                        Reverse OFF
                    Count: 3


-------------------------------------------------------------------------------
Address 6D: Trunk Elect.        Labels: None
   Part No SW: 4L0 910 945     HW: 4L0 827 851 B
   Component: ValeoHeckdeckel H21 0280  
   Revision: --H21001    Serial number: E5030000B     
   Shop #: WSC 98765 666 38354
   VCID: 6C81C543AA8320D705D-8038

   Subsystem 1 - Part No: 4L0 910 946 
   Component: ValeoHeckdeckel H21 0280

   Subsystem 2 - Serial number: E5030100B     

   Subsystem 3 - Serial number: RD05.04.07--H21001001A0151ÿ

   Subsystem 4 - Serial number: 1A0151ÿ

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: 002625927-----
   Coding: 0003591
   Shop #: WSC 31414 790 00001
   VCID: 2615F76B74EFDA87939-8072

   Subsystem 1 - Part No: 4L0 910 591 
   Component: J_245_EE15_SKB09H10 0180

   Subsystem 2 - Part No: 4L0 910 591 
   Component: J_394_EE15_SKB09H10 0180

   Subsystem 3 - Part No: 4L0 910 591 
   Component: J_392_EE15_SKB09H10 0180

1 Fault Found:
02915 - Sensor 2 for Trunk/Hatch Closed (G526) 
            010 - Open or Short to Plus
             Freeze Frame:
                    Fault Status: 01101010
                    Fault Priority: 1
                    Fault Frequency: 2
                    Reset counter: 98
                    Mileage: 200913 km
                    Time Indication: 0
                    Date: 2020.03.02
                    Time: 15:56:32


-------------------------------------------------------------------------------
Address 72: Door, Rear Right        Labels: 4L0-910-795.lbl
   Part No SW: 4L0 910 795 C    HW: 4L0 959 794 C
   Component: TSG HR          H21 0050  
   Coding: 0000002
   Shop #: WSC 31414 790 00001
   VCID: 323D1B3B4827B6270F1-8066

No fault code found.

-------------------------------------------------------------------------------
Address 76: Park Assist        Labels: 4Fx-910-283.lbl
   Part No SW: 4F0 910 283 G    HW: 4F0 919 283 G
   Component: Parkhilfe 8-Kan H12 0060  
   Revision: 00H12000    Serial number: 06330707802696
   Coding: 0221046
   Shop #: WSC 31414 790 00001
   VCID: 2809F9537EFBCCF7A15-807C

No fault code found.

-------------------------------------------------------------------------------
Address 77: Telephone
Cannot be reached

End----(Elapsed Time: 02:02, VBatt start/end: 11.9V/11.9V. VIgn 11.9V)-----
 
   #2  

HMC

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What is the fuel rail pressure when cranking? No pressure = no injectors!
Regards HMC
 
   #3  

naushad2982

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Injectors will only start firing when a minimum of 280 bar has been achieved on the fuel rail, Group 001 of the measured value blocks while cranking will give you fuel rail pressure readings.... Also you guys are right hand drive like us in Kenya so its also possible the ECU has water damage. those things are mounted in the absolute worst place. seen an 07 Q7 exactly like you described. getting fuel pressure and everything still wouldn't start
 
   #4  

ClisbyAutoElectrical

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Thanks for the Info, Ill recheck and let you know what i find
 
   #5  

ClisbyAutoElectrical

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OK so looking at the fuel pressure sensor, in the measuring block i have a constant fuel pressure of 7.1 bar regardless of whether the vehicle is cranking or not. I also checked the signal coming from the pressure sensor to the ECU with an oscilloscope under cranking and the waveform started rising, but still no change on the measuring blocks. This made me suspect a broken wire to the ECU, but as soon as i unplugged the pressure sensor i had a fault code for an open circuit sensor, and the pressure in the measuring blocks changed. So i'm thinking it could be a faulty pressure sensor, does anyone know the range that the sensor operates within so that i can check it with a scope with some form of data to reference. I suppose it still could also be the ECU itself. I have removed the ECU and visually inspected both the connectors on the car side, and the ECU and there were no signs of water damage, at least externally anyway.
 
   #6  

HMC

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"with an oscilloscope under cranking and the waveform started rising". What voltage did it rise to? If you are suspecting a fault on the sensor signal wire you need to load test it at the ECU connector, using the correct wiring diagram. Do you have the equipment to physically test the rail pressure?
Regards HMC
 
   #7  

Gremling

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Hi,
This might be severel things, I can think of a few, all easily to check with correct and relatively cheap equipment. Having said this, I do not think the glow plug illuminating sign in dash, is for glow plug themselves, as they are not on/active when engine is warm, but more uses that sign as an indicator of error in system.
Also keep in mind that an second fault might have been incorporated into engine, during fiddling with wires.
I suspect that a faulty Turbo control function (stuck vane rings or control rod etc) would give the code you have. Furthermore I am wondering if an Exhaust gas recirculation potentiometer G212, or incorrect signal from this one, would cause the Glow-plug sign to show up, and cause limp home.

1) Try to use the VCDS and operate turbo Audi vane controller (should be in basic settings and a drop down choice). This will tell if turbo controller works correctly, and then check visually that the actuator rod physically moves, turning ring for guide vanes.
2) Use the VCDS and check all temp sender (EGT/Inlet/EGR) sends signals that computes with what they should "see"
3) Check fuel rail pressure with gauges, and compare to reading in VCDS, ensure gauges are suitable for max system pressure, and then some. A leak in injector(s) will cause lack of pressure build-up -> No fuel (correctly vaporized) injected and therefore no bang. This test will tell if G247 is working or corresponding to live gauges. It will also tell if HP pump is working at all.
4) A leak from N276 (Fuel press Control valve on CR front side of right side bank) can also cause lack of pressure, is a bit more tricky, but doing a test as in 1) then isolation bank 1 (the one with the adjusting valve) and see in pressure gets higher.
5) Not sure weather fault in Address 61: Battery Regulator can cause issues for you, but worth investigating, and maybe also check that car is not into some sort of transport mode (energy saving mode) after that fault code locked in.

Also read the SSP 479 VAG SelfStudyProgram 479 and also 495, both for the 3.0L V6 TDI engine 2nd generation. https://cardiagn.com/vag-self-study-program-ssp/

Regards
Gremling
 
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