Q7 q7 3.0 tdi wont start please help

bolt123

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Hi we have a q7 in at the min with a non start issue. The vehicle cranks just will not fire.

So far we have found on vcds that there is no fault codes apart from glow plugs 6 open circuit we are however getting no fuel pressure. We are getting a good flow from tank to the pump the belt on the pump is ok.

The cranking rpm was slow 147 rpm so we have replaced the starter now it's cranking alot better at 250 rpm.

The pump has been taken off and checked the shaft and the imv for swarf all seems fine. If we have the imv in no fuel will come through however pulling the plug off allows diesel to flow through into the hp pipes. Still no pressure.

If we unplug the pressure sensor we are getting default 350 bar. We have also connected it to the airline getting about what the compressor is reading (that's while connected to the car)

I've now blanked the fuel return valve at the end of the fuel Rail which is still hasn't helped.

My next move is to do a leak test and my worry is ecu failure? Can any shed any light or suggest anything that I should be doing? I'm pritty new on the vcds.

Kind regards
 
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------



Chassis Type: 4L (4L0)

Scan: 01 02 03 05 07 08 09 0E 15 16 17 18 19 34 37 42 46 47 4F 52

56 61 62 6D 6F 72 76

VIN: WAUZZZ4L97D033911 Mileage: 274050km-170286miles

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: 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: OK 0000

19-CAN Gateway -- Status: OK 0000

34-Level Control -- 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: OK 0000

62-Door, Rear Left -- Status: OK 0000

6D-Trunk Elect. -- Status: OK 0000

6F-Centr. Conv. II -- Status: OK 0000

72-Door, Rear Right -- Status: OK 0000

76-Park Assist -- Status: OK 0000



-------------------------------------------------------------------------------

Address 01: Engine Labels: 059-907-401-ASB.clb

Part No SW: 4L0 910 401 M HW: 4L0 907 401

Component: 3.0L V6TDI G001AG 0030

Revision: --H03--- Serial number:

Coding: 0011775

Shop #: WSC 00502 210 91521

VCID: 2C509C9F8F18905ED1-8078

1 Fault Found:

005663 - Glowplug for Cylinder 6 (Q15)

P161F - 001 - Open Circuit

Freeze Frame:

Fault Status: 01100001

Fault Priority: 0

Fault Frequency: 1

Reset counter: 255

Mileage: 274053 km

Time Indication: 0

Date: 2006.03.16

Time: 09:56:31

Freeze Frame:

RPM: 0 /min

Torque: 0.0 Nm

Speed: 0.0 km/h

Duty Cycle: 1.0 %

Voltage: 11.48 V

Duty Cycle: 15.0 %

Temperature: 15.3°C

Readiness: 0 0 1 1 1

-------------------------------------------------------------------------------

Address 02: Auto Trans Labels: 09D-927-750.lbl

Part No SW: 09D 927 750 FK HW: 09D 927 750 FK

Component: AL 750 6A 0940

Revision: 00H52000 Serial number:

Coding: 0000504

Shop #: WSC 31414 790 00001

VCID: 7CF06CDF3FF8C0DE01-8028

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: 00H21001

Coding: 0038033

Shop #: WSC 31414 790 00001

VCID: 2858608F9BE0BC7E35-807C

1 Fault Found:

01826 - Sensor for Steering Angle (G85); Supply Voltage Terminal 30

000 - -

Freeze Frame:

Fault Status: 01100000

Fault Priority: 2

Fault Frequency: 1

Reset counter: 180

Mileage: 274053 km

Time Indication: 0

Date: 2006.03.16

Time: 10:07:13

Freeze Frame:

Count: 128

Count: 4353

Count: 297

Count: 44544



-------------------------------------------------------------------------------

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: 10601000480461

Coding: 0000147

Shop #: WSC 00502 210 91535

VCID: 63C237A3A2461F2620-8036

Subsystem 1 - Part No: 4F0 910 131 E

Component: FBSAUDIC6 EZS H45 0080

Subsystem 2 - Part No: 4F0 910 220 D

Component: FBSAUDIC6 IDG H01 0040

No fault code found.

-------------------------------------------------------------------------------

Address 07: Control Head Labels: 4L0-910-7xx-07-H.lbl

Part No SW: 4L0 910 731 K HW: 4E0 035 729

Component: Interfacebox H43 4220

Revision: 00000000 Serial number: 386GW067515732

Coding: 0002002

Shop #: WSC 31414 790 00001

VCID: 306888EFA330F4BEED-8064

Subsystem 1 - Part No: 4F0 910 609 E

Component: Bedienteil MMIC6H02 0050

Subsystem 2 - Serial number: 00000000220048

Subsystem 3 - Serial number: 0125.08.050000000100010441ÿ

Subsystem 4 - Serial number: 010441ÿ

1 Fault Found:

00658 - Control Head

008 - Implausible Signal

Freeze Frame:

Fault Status: 01101000

Fault Priority: 7

Fault Frequency: 1

Reset counter: 180

Mileage: 274053 km

Time Indication: 0

Date: 2006.03.16

Time: 10:07:57

Freeze Frame:

Bin. Bits: 100



-------------------------------------------------------------------------------

Address 08: Auto HVAC Labels: None

Part No SW: 4L0 910 043 HW: 4L0 820 043 E

Component: KLIMABETAETIGUNGH05 0040

Revision: 00---008 Serial number: 00000000050068

Coding: 0001046

Shop #: WSC 31414 790 00001

VCID: 61CE3DABB85A0D3632-8034

3 Faults Found:

01810 - Actuating Motor for Temperature Flap; Right (V159)

003 - Mechanical Failure

Freeze Frame:

Fault Status: 01100011

Fault Priority: 3

Fault Frequency: 1

Reset counter: 180

Mileage: 274053 km

Time Indication: 0

Date: 2006.03.16

Time: 10:08:20

Freeze Frame:

Voltage: 12.20 V

Temperature: 18.0°C

(no units): 193.0

(no units): 73.0

Temperature: 18.0°C

00712 - Right Footwell Flap Positioning Motor (V109)

003 - Mechanical Failure

Freeze Frame:

Fault Status: 01100011

Fault Priority: 3

Fault Frequency: 1

Reset counter: 180

Mileage: 274053 km

Time Indication: 0

Date: 2006.03.16

Time: 10:08:20

Freeze Frame:

Voltage: 12.20 V

Temperature: 18.0°C

(no units): 18.0

(no units): 130.0

Temperature: 18.0°C

01809 - Actuating Motor for Temperature Flap; Left (V158)

003 - Mechanical Failure

Freeze Frame:

Fault Status: 01100011

Fault Priority: 3

Fault Frequency: 1

Reset counter: 180

Mileage: 274053 km

Time Indication: 0

Date: 2006.03.16

Time: 10:08:20

Freeze Frame:

Voltage: 12.20 V

Temperature: 18.0°C

(no units): 183.0

(no units): 140.0

Temperature: 18.0°C



-------------------------------------------------------------------------------

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: 0011101

Shop #: WSC 31414 790 00001

VCID: 316E8DEBA83AFDB6E2-8064

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 910 111 A HW: 4L0 035 111

Component: CD-Changer H41 0100

Revision: 00000000 Serial number: AUZ5ZBF3026191

Shop #: WSC 00000 000 00000

VCID: 1E344657C9A472CE4F-804A

No fault code found.

-------------------------------------------------------------------------------

Address 15: Airbags Labels: 4L0-910-655.lbl

Part No SW: 4L0 910 655 B HW: 4L0 959 655

Component: 31 AIRBAG AUDI8RH38 0120

Revision: 05H38000 Serial number: 0037GD06DNNI

Coding: 0013105

Shop #: WSC 31414 790 00001

VCID: 2C509C9F8F18905ED1-8078

Subsystem 1 - Serial number: 6332QSME124C7739K

Subsystem 2 - Serial number: 6342QSME10233C131

Subsystem 3 - Serial number: 6352QSME124D4571E

Subsystem 4 - Serial number: 6362QSME12544B2DK

Subsystem 5 - Serial number: 63734SME116E3E5BD

Subsystem 6 - Serial number: 63834SME11782811V

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: 90054061900604

Coding: 0102142

Shop #: WSC 31414 790 00001

VCID: 66C42EB751746A0EC7-8032

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 920 980 G

Component: KOMBIINSTR. M73 H17 0110

Revision: 00300000 Serial number: 5HJ30XM76

Coding: 2593443

Shop #: WSC 80093 222 71269

VCID: 234277A3E2C65F2660-8076

No fault code found.

-------------------------------------------------------------------------------

Address 18: Aux. Heat Labels: None

Part No SW: 4L0 910 105 HW: 4L0 815 071 C

Component: Heizgeraet H07 0060

Revision: 0000000E Serial number: 00000009011043

Coding: 0000002

Shop #: WSC 31414 790 00001

VCID: 60C838AFB350043E3D-8034

No fault code found.

-------------------------------------------------------------------------------

Address 19: CAN Gateway Labels: 4L0-910-468.lbl

Part No SW: 4L0 910 468 HW: 4L0 907 468

Component: J533__Gateway H06 0040

Revision: 00H06000 Serial number: 0900B067178099

Coding: F55BBE5F302202

Shop #: WSC 00502 210 91521

VCID: 6CD05C9F4F98505E91-8038

No fault code found.

-------------------------------------------------------------------------------

Address 34: Level Control Labels: None

Part No SW: 4L0 910 553 B HW: 4L0 907 553

Component: LUFTFDR.-CDC H03 7550

Revision: --H03001 Serial number: 15.1528-0095.2

Coding: 0015510

Shop #: WSC 31414 790 00001

VCID: 295E658B80EA85762A-807C

No fault code found.

-------------------------------------------------------------------------------

Address 37: Navigation Labels: 4E0-910-88x-37.lbl

Part No SW: 4E0 910 887 Q HW: 4E0 919 887 D

Component: MNS ECE H48 0850

Revision: 00000000 Serial number: 399GV067530424

Shop #: WSC 31414 790 00001

VCID: 3B72AFC37A7607E648-806E

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 0130

Revision: 00000000 Serial number: ˆy


Coding: 0002651

Shop #: WSC 31414 790 00001

VCID: 2F6A8B93BE0EEB46F4-807A

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 H08 0060

Revision: 0060 --- Serial number: 01903971940000

Coding: 7348475

Shop #: WSC 80093 222 69422

VCID: 336287E35226CFA690-8066

Subsystem 1 - Part No: 1K0 951 605 C

Component: LIN BACKUP HORN H03 1301

Subsystem 2 - Part No: 4F0 910 177

Component: Innenraumueberw.H01 0020

No fault code found.

-------------------------------------------------------------------------------

Address 47: Sound System Labels: Redir Fail!

Part No SW: 4L0 910 223 B HW: 4L0 035 223

Component: DSP-AU716 H20 0100

Revision: 11S00001 Serial number: 01607060321714

Coding: 0000003

Shop #: WSC 31414 790 00001

VCID: 234277A3E2C65F2660-8076

No fault code found.

-------------------------------------------------------------------------------

Address 4F: Centr. Electr. II Labels: 4F0-910-280.lbl

Part No SW: 4F0 910 280 HW: 4F0 907 280 E

Component: ILM Beifahrer H10 0080

Revision: Serial number: 00000000002404

Coding: 0011101

Shop #: WSC 31414 790 00001

VCID: 5EB40657892432CE0F-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 0130

Revision: 00000000 Serial number: 3 ‚

Coding: 0002651

Shop #: WSC 31414 790 00001

VCID: 2F6A8B93BE0EEB46F4-807A

No fault code found.

-------------------------------------------------------------------------------

Address 56: Radio Labels: 4E0-910-541.lbl

Part No SW: 4E0 910 541 Q HW: 4E0 035 541 P

Component: TUNER EU/US/RDW H42 0620

Revision: 00000000 Serial number: 388G4067539883

Coding: 0000001

Shop #: WSC 31414 790 00001

VCID: 2E549697B904E24EFF-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: 00000000030231

Shop #: WSC 31414 790 00001

VCID: 64C034BFA748181ED9-8030

Subsystem 1 - Part No: 4F0 915 105 D

Component: von VA0 2607171156

Coding: 344630393135313035442056413032363037313731313536

Shop #: WSC 31414 790 00001

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 0050

Coding: 0002058

Shop #: WSC 31414 790 00001

VCID: 316E8DEBA83AFDB6E2-8064

No fault code found.

-------------------------------------------------------------------------------

Address 6D: Trunk Elect. Labels: None

Part No SW: 4L0 910 945 HW: 4L0 827 851 A

Component: ValeoHeckdeckel H20 0280

Revision: --H20001 Serial number: E5030000B

Shop #: WSC 98765 666 38354

VCID: 6CD05C9F4F98505E91-8038

Subsystem 1 - Part No: 4L0 910 946

Component: ValeoHeckdeckel H20 0280

Subsystem 2 - Serial number: E5030100B

Subsystem 3 - Serial number: RD25.07.06--H20001000B0200ÿ


Subsystem 4 - Serial number: 0B0200ÿ

No fault code found.

-------------------------------------------------------------------------------

Address 6F: Centr. Conv. II Labels: 4L0-910-290.lbl

Part No SW: 4L0 910 290 HW: 4L0 907 290

Component: ILM HINTEN 2 H05 0060

Revision: AAH05061 Serial number: 001845038-----

Coding: 0000001

Shop #: WSC 31414 790 00001

VCID: 65C629BBAC726116CE-8030

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 0050

Coding: 0002058

Shop #: WSC 31414 790 00001

VCID: 316E8DEBA83AFDB6E2-8064

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: 06320620100569

Coding: 0201146

Shop #: WSC 31414 790 00001

VCID: 2858608F9BE0BC7E35-807C

No fault code found.

End-------------------------(Elapsed Time: 03:18)--------------------------
 
Hi thanks for the reply im just trying not to waste to much money as it has now had a battery and starter. It all seems to be down to the metering valve n290 when connected the vehicle is not allowing any fuel through and from what I gather it will only allow a small quantity through when disconnected. I don't think we have an immobiliser issue as ive read the car will start and shut off with a symbol on the dash.

The early events on this vehicle was that it did crank a fair while before starting this was put down (by the owner) to the battery not being full, However a new battery didn't cure it but a new starter has definitely made a big difference the car sounds a lot more lively but still failing to start
 
Yes if there is an immo problem cars usually start for a few seconds before cutting out an will raise a CEL with an associated code.
 
Yer I'm sort of moving away from the immobiliser. It's this fuel problem where nothing will come through if the metering valve (n290) is connected and does when you unplug it. I've read that when unplugged it will allow a small amount of fuel through. Not sure weather it is enough to start it though. I wonder if there's a fuel cut off switch that be triggered.
 
Ecu failure on the q7 is common due to where the ecu is positioned. Had one in a month ago and it has blown the ecu however I had no contact with it on the scanner...
 
Yes pump has been off and valve out I've also made a blanking plate to totally do away with it hoping to get something.
The thing that is bugging me is that it's showing no fuel pressure but there is no fault code. Now Inless it's stopping the fuel pressure itself so knows that it isn't a fault as it's doing it
 
  • Like
Reactions: Skids1
Hi did you get the problem sorted as my Q7 is doing the same thing?
 
Yes pump has been off and valve out I've also made a blanking plate to totally do away with it hoping to get something.
The thing that is bugging me is that it's showing no fuel pressure but there is no fault code. Now Inless it's stopping the fuel pressure itself so knows that it isn't a fault as it's doing it
Hi did you get the problem sorted? My Q7 is doing the same with no faults
 
Hello,
I have the same problem : won't start

Starter turn but engine won't start
I have no pressure after HP pump!
No fault find with VCDS.
Engine bks 2007.

If you have any information or if you have find the problem I'am interested!
 
Reviving this thread because I’m having this problem. Anyone get their Q7 to work? I’ve changed glow plugs, fue filter, and crank position sensor. I’m running out of ideas and money.


Sent from my iPhone using Tapatalk
 
I’m in the same position - the diesel engineers here have confirmed the hpfp is pumping within spec when they bench test it but on the car, no fuel pushes out on the other end... there must be a sensor or trigger somewhere that tells the pump to work???
 
I’m in the same position - the diesel engineers here have confirmed the hpfp is pumping within spec when they bench test it but on the car, no fuel pushes out on the other end... there must be a sensor or trigger somewhere that tells the pump to work???

Mine ended up being a coolant temp sensor that was messing my Q7 up. Not fuel related but could work I guess.


Sent from my iPhone using Tapatalk
 
I have seen some posts saying that the coolant sensor could be it - I will have to pull mine out and get a new one and keep my fingers crossed!
I do have VCDS but I have no clue as to which measuring block to check for my 3.0 TDI (BUG engine) for the coolant temp
There is however a temp reading that shows over 500 degrees celcius (so I may as well change the sensors and swing it)
 
So I got the coolant sensor today - just shy of R900 (South African Rands) including the o-ring and spring clip and I’ll drop it in soon - maybe tomorrow morning if the weather permits. Hopefully I have the same luck as you :)
 
  • Like
Reactions: i3oricua
I've just had a no-start situation as described above: crank, no-start, zero pressure in common rail and no faults. It was the N290. It is also a good idea to change the N276 (I changed mine four months ago). You can source N290 separately (no need to buy the pump), but it may be a little difficult to remove (intake manifold, swirl flaps and HP piping need to go to gain access), and the three bolts holding the sensor were super seized on mine!

N290 reports fine in diag, and yet it is sticking intermittently.

2007 Q7, BUG, with 170km
 
So I got the coolant sensor today - just shy of R900 (South African Rands) including the o-ring and spring clip and I’ll drop it in soon - maybe tomorrow morning if the weather permits. Hopefully I have the same luck as you :)
FYI - I was not so lucky - temperature sensors not the issue
 
The N290 is 059906457 and the N276 is 057130764F.

Yes, the G62/G83 did not help, I changed them too.

 
A6 A6 ecu Hi there guys, reviving one more time this thread.I already changed N290 but with no luck.It was one from another car but I doubt the possibility of finding another one with the same issue.My car is Audi A6 2.7 tdi with the same HP pump that Q7 2008 has.The second fuel pump was disconnected without me knowing and I thought there was something else related.I cranked the engine several times without fuel and I don't what happened.I searched for metal shavings in the pump, it is pristine clean.Changed N276 and N290, no luck.I have 7 bars at ignition on and no improvement when cranking.
 
View attachment 174429 View attachment 174430 Hi there guys, reviving one more time this thread.I already changed N290 but with no luck.It was one from another car but I doubt the possibility of finding another one with the same issue.My car is Audi A6 2.7 tdi with the same HP pump that Q7 2008 has.The second fuel pump was disconnected without me knowing and I thought there was something else related.I cranked the engine several times without fuel and I don't what happened.I searched for metal shavings in the pump, it is pristine clean.Changed N276 and N290, no luck.I have 7 bars at ignition on and no improvement when cranking.


Hi, I have the same problem as yours. 7.1 bars on ignition. 71 bars while cranking, sometimes 170 bars but it doesn't enough to start the car. Did you fix your problem?
 
I have a mate who runs a car repair business, his speciality is BMWs but one of his customers wanted a Q7 3.0 TDI serviced which included a fuel filter. After replacing the filter he couldn't get the car to start. In frustration and having run out of ideas (been in the trade for nigh on 50 years) he phoned the local main dealer who admitted it was a known problem and they didn't change the filter even on major services (bet they charged for it!). There is some sort of air-lock issue that requires a lot of faffing around to overcome.
 
Hi.

I have the same problem on 2008 3.0tdi.
Difference is I have over 300bar on starter but will not fire when hot.
When cold it starts imidiatly.
New HP pump and filter.
Any toughts??
 
Hi we have a q7 in at the min with a non start issue. The vehicle cranks just will not fire.

So far we have found on vcds that there is no fault codes apart from glow plugs 6 open circuit we are however getting no fuel pressure. We are getting a good flow from tank to the pump the belt on the pump is ok.

The cranking rpm was slow 147 rpm so we have replaced the starter now it's cranking alot better at 250 rpm.

The pump has been taken off and checked the shaft and the imv for swarf all seems fine. If we have the imv in no fuel will come through however pulling the plug off allows diesel to flow through into the hp pipes. Still no pressure.

If we unplug the pressure sensor we are getting default 350 bar. We have also connected it to the airline getting about what the compressor is reading (that's while connected to the car)

I've now blanked the fuel return valve at the end of the fuel Rail which is still hasn't helped.

My next move is to do a leak test and my worry is ecu failure? Can any shed any light or suggest anything that I should be doing? I'm pritty new on the vcds.

Kind regards
did you fix your q7 mine is doing the same
 
Tryed to change the CPS but made no difference. Starts imidiatly when cold. Stalls when it reaches operating temperature.
Tryed to unplug the coolant temperature sensor.
This resulted in the fan blowing all the time and engine not reaching operating temperature. The engine did not stall.
Put the plug back on and as soon the engine got operating temp, it stalls...