walko789

Hello all, looking for some help and cant seem to find a solution on the forum that has caused this fault and had it resolved but I could have missed it.
I have a 2007 A8L with 95k miles on it and owned it since new. It was time for routine service a few weeks ago so I took it in. The tech who has worked on the car since it was new advised me that he thought I might be needing a new fuel pump, but not to worry about it yet unless I start to have problems. A day later the engine light came on and back to service it went. Tech believed that it was a fuel pump due to an error code he saw. We have now replaced both fuel pumps, the fuel filter and the senor. Seems the car will drive for about 20 miles and then the engine light pops back on with the code P0087. It continues to occur (and stays lit until reset). I noticed it in a right hand turn when I pushed down the accelerator and it was also noticed right at the bottom of a hill going up. And the mystery deepens- car has never stalled or sputtered. Before the new fuel pumps, it was noted that occasionally (1 in 3 starts) ignition would take a bit longer than "normal" to catch and turnover, but it always turned over. The tech suspects a voltage issue and this means a possible replacement of the module. I am pouring $$$ and brain cells into this as well as the tech. Has anyone had this issue before? Suggestions please.

dvs_dave

Sounds like you're using a generic code reader? What does a proper VCDS scan show?

At a guess that code is low fuel pressure or lean mixture?

Have you run a few bottles of injector cleaner like techron through it? That seems to remedy fuelling issues like this on the DI engines.

walko789

thank you dvs Dave. I am using VCDS- please see full below- I have not yet run injector cleaner- I did see several suggestions in the forum. In the past I have used BG44K.

Here are all of the faults:

Address 01: Engine Labels: Redir Fail!
Part No SW: 4E1 910 560 A HW: 4E1 907 560
Component: 4.2l V8/4V 0050
Revision: 71H25--- Serial number: AUX3Z0F4795103
Coding: 01060009190F0120
Shop #: WSC 20112 444 83955
VCID: 20446669F32FCE214EF-8075

1 Fault Found:
000135 - Fuel Rail/System Pressure
P0087 - 008 - Too Low - Intermittent - MIL ON
Freeze Frame:
Fault Status: 10101000
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 153260 km
Time Indication: 0
Date: 2015.04.04
Time: 11:37:49

Freeze Frame:
RPM: 2425 /min
Load: 82.7 %
Speed: 87.0 km/h
Temperature: 94.0°C
Temperature: 23.0°C
Absolute Pres.: 850.0 mbar
Voltage: 14.224 V
Address 07: Control Head Labels: 4E0-910-7xx-07.lbl
Part No SW: 4E0 910 731 K HW: 4E0 035 729 A
Component: Interfacebox H43 2740
Revision: 00000000 Serial number: 348EQ067503715
Coding: 0000003
Shop #: WSC 02313 785 00200
VCID: 29527B4D80150F69191-807C

Subsystem 1 - Part No: 4E0 910 611
Component: E0380 BedienteilH03 0040

Subsystem 2 - Serial number: 00000000011319

Subsystem 3 - Serial number: 0109.06.060000000100010055ÿ

Subsystem 4 - Serial number: 010055ÿ

1 Fault Found:
01327 - Control Module for Parking Aid (J446)
004 - No Signal/Communication - Intermittent
Freeze Frame:
Fault Status: 00100100
Fault Priority: 5
Fault Frequency: 15
Reset counter: 185
Mileage: 153077 km
Time Indication: 0
Date: 2015.03.29
Time: 13:47:32

Address 08: Auto HVAC Labels: None
Part No SW: 4E0 910 043 B HW: 4E0 820 043 H
Component: KLIMAAUTOMAT 017 0450
Revision: 00000032 Serial number: 00000000098890
Coding: 0102737
Shop #: WSC 02311 785 00200
VCID: 1C3C5299DF47EAC1927-8049

Subsystem 1 - Part No: 4E0 910 772 A
Component: Sitzluefter FS H02 010

Subsystem 2 - Part No: 4E0 910 772 A
Component: Sitzluefter BFS H02 010

Subsystem 3 - Serial number: 898053000

Subsystem 4 - Serial number: HO07062006065A000000000326ÿ†89

Subsystem 5 - Serial number: 000326ÿ†898053000 000-SHO

Subsystem 6 - Serial number: 000-SHO06062006065A00000000

Subsystem 7 - Serial number: 65A000000000236ÿ

1 Fault Found:
00066 - Rear Right Footwell Heater (Z43)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 128
Mileage: 153007 km
Time Indication: 0
Date: 2015.03.26
Time: 10:50:26

Freeze Frame:
Voltage: 11.20 V

Address 37: Navigation Labels: 4E0-910-88x-37.lbl
Part No SW: 4E0 910 888 C HW: 4E0 919 887 D
Component: MNS US H48 0960
Revision: 00000000 Serial number: 381EP067500738
Shop #: WSC 02313 785 00200
VCID: 2E588851B9FB6851CC3-807B

1 Fault Found:
02870 - Function Restricted due to Faulty Data
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 7
Fault Frequency: 1
Reset counter: 178
Mileage: 153164 km
Time Indication: 0
Date: 2015.03.31
Time: 15:45:27

Freeze Frame:
Hex Value: 0x551A
Hex Value: 0xC117
Hex Value: 0x0200
Hex Value: 0x0000

thank you in advance

dvs_dave

I'd still suggest running a few tanks of fuel with plenty of injector cleaner in them as my first fix. If no change and there are no apparent running issues, I'd then suggest it was a fuel low pressure sensor problem. Have a look here
http://www.jimellisaudiparts.com/showAssembly.aspx?ukey_assembly=747105&ukey_produc t=5410714

Component 21 in the diagram. Try unplugging it and running the engine. Aside from the codes thrown by the disconnected sensor, does the low pressure error go away?

walko789

thank you dvs dave!

dvs_dave

More diagnosis info can be found here around this problem with sensor G410

http://www.brakeandfrontend.com/tech-tip-audi-has-mil-on-with-multiple-low-fuel-pressure-dtcs/

mishar

That pressure sensor is inexpensive and easy to replace. I would suggest that.

walko789

thank you mishar!

dvs_dave

+1, replace that sensor and tell us how you get on. Its used on numerous VAG group engines and appears to be a well known problem item.

walko789

we have replaced , in order, both in tank fuel pumps, G410 module and fuel filter and added one can BG 44k with 1/2 tank of gas in the in car. I have cleared the fault. If it reoccurs before plan of action completed, I will clear and continue with plan. Plan of action is to use up 1/4 tank of gas (leaving 1/4 in the car-some highway and city miles) then fill up and add another can of BG. fingers crossed...will keep you posted