Hi guys, usually on here for my A8 D3, but tonight my GF's 2001 A6 2.7TT broke down on the way home. I think I've ruled out cambelt (chain?) and alternator belt.

Symptoms:
Lost power on the road, spluttered, 'jerking' and 'trying to go, but had no power. It would go, then loose power, then go again' (her words)...all electrical ancillaries worked, but battery light came on, and power steering reduced with lost power.

Now:
Starts right up, runs briefly, cuts out.
Has oil, coolant etc.
Sounds like fuel pump/injectors to me

Ran a quick Vag Com on it, and that has not been done since we bought it a year ago. The catalyst codes listed are periodic, throw an engine management light, and I've cleared just those with a hand held code reader maybe a half dozen times.

Reverse light code is (I'm pretty sure) a stuck plunger switch in the side of the gear box. I have a replacement to put in.

Help me out please guys, I'm a bit lost!

Scan results:

Thursday,23,February,2012,22:15:04:40451
VCDS Version: Release 11.11.2 (x64)
Data version: 20120126



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


Chassis Type: 4B - Audi A6 C5
Scan: 01 02 03 06 08 15 16 17 18 22 34 35 36 37 45 55 56 57 65 67
75 76 77

VIN: WAULD64B82N015963
-------------------------------------------------------------------------------
Address 01: Engine Labels: 078-907-551-AZA.lbl
Part No: 4B0 907 551 AK
Component: 2.7l V6/5VT G 0001
Coding: 06712
Shop #: WSC 02325
VCID: 6DDBF8D7278ADFB
WAULD64B82N015963 AUZ7Z0A1881780

2 Faults Found:
16805 - Warm Up Catalyst; Bank 1
P0421 - 35-10 - Efficiency Below Threshold - Intermittent
16815 - Warm Up Catalyst; Bank 2
P0431 - 35-00 - Efficiency Below Threshold
Readiness: 0000 0000

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 4B0-614-517.lbl
Part No: 4B0 614 517 H
Component: ABS/ESP allrad 1328
Coding: 06395
Shop #: WSC 02325
VCID: 2649C7FBC2FC2C3

No fault code found.

-------------------------------------------------------------------------------
Address 06: Seat Mem. Pass Labels: None
Part No: 4B0 959 760 C
Component: Sitzmemory R1 BF 0102
Coding: 00003
Shop #: WSC 00000
VCID: 2D5B38D7E70A1FB

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 4B0-820-043-MY2.lbl
Part No: 4B0 820 043 AD
Component: A6-Klimavollautomat 0104
Coding: 00010
Shop #: WSC 02325
VCID: 5CBDA513CC30A63

7 Faults Found:
01272 - Positioning Motor for Central Flap (V70)
41-10 - Blocked or No Voltage - Intermittent
00716 - Air recirculation Flap Positioning Motor (V113)
41-10 - Blocked or No Voltage - Intermittent
01274 - Air Flow Flap Positioning Motor (V71)
41-10 - Blocked or No Voltage - Intermittent
00735 - Potentiometer in Positioning Motor for Air recirculation Flap (G143)
30-10 - Open or Short to Plus - Intermittent
00819 - High Pressure Sensor (G65)
07-00 - Signal too Low
01592 - Air Quality Sensor (G238)
57-00 - Electric Circuit Failure
01317 - Control Module in Instrument Cluster (J285)
49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 4B0-959-655-AI84.lbl
Part No: 4B0 959 655 N
Component: Airbag 8.4E 3000
Coding: 0000307
Shop #: WSC 02325 785 00200
VCID: 3B7F068F797E81B

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 4B0-907-487.lbl
Part No: 4B0 907 487 C
Component: Lenkradelektronik D01
Coding: 00002
Shop #: WSC 02325
VCID: 2C5D35D3DC10163

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 4B0-920-xxx-17.lbl
Part No: 4B0 920 983 FX
Component: KOMBI+WEGFAHRS. VDO D17
Coding: 02264
Shop #: WSC 08213
VCID: 830F3E6F910EB9B
WAULD64B82N015963 AUZ7Z0A1881780

No fault code found.

-------------------------------------------------------------------------------
Address 35: Centr. Locks Labels: 4B0-962-258.lbl
Part No: 4B0 962 258 J
Component: Central Lock/Alarm D34
Coding: 15885
Shop #: WSC 08213
VCID: 306521A3F038723

11 Faults Found:
01366 - Opened Due to Crash Signal
35-00 - -
01371 - Alarm triggered by Door Contact Switch; Driver's Side
35-00 - -
01572 - Alarm triggered by Door Contact Switch; Passenger Side
35-00 - -
01374 - Alarm triggered by Terminal 15
35-00 - -
01370 - Alarm triggered by Interior Monitoring
35-00 - -
01369 - Alarm triggered by Hood Switch
35-00 - -
00955 - Key 1
09-10 - Adaptation Limit Surpassed - Intermittent
00956 - Key 2
09-10 - Adaptation Limit Surpassed - Intermittent
01561 - Left Rear Door
59-00 - Can't Unlock
01562 - Right Rear Door
59-10 - Can't Unlock - Intermittent
01573 - Alarm triggered by Door Contact Switch; Left Rear
35-00 - -

-------------------------------------------------------------------------------
Address 36: Seat Mem. Drvr Labels: None
Part No: 4B0 959 760 B
Component: Sitzmemory R1 F 0101
Coding: 00001
Shop #: WSC 00000
VCID: 2C5D35D3DC10163

No fault code found.

-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: None
Part No: 4B0 951 178 A
Component: Innenraumueberw. D04
Coding: 00101
Shop #: WSC 02325
VCID: 2649C7FBC2FC2C3

No fault code found.

-------------------------------------------------------------------------------
Address 55: Xenon Range Labels: 4Z7-907-357.lbl
Part No: 4Z7 907 357
Component: dynamische LWR D06
Coding: 00050
Shop #: WSC 02325
VCID: 040DBD7314003E3

1 Fault Found:
00776 - Level Control System Sensor; Left Front (G78)
31-00 - Open or Short to Ground

-------------------------------------------------------------------------------
Address 56: Radio Labels: 8E0-035-1xx-56.lbl
Part No: 4B0 035 195 J
Component: symphony II NP2 0008
Coding: 00201
Shop #: WSC 00000
VCID: 2757CAFFC5F635B

No fault code found.

-------------------------------------------------------------------------------
Address 76: Park Assist Labels: 8Z0-919-283.lbl
Part No: 8Z0 919 283
Component: Parkingsyst. A6 USA D08
Coding: 00126
Shop #: WSC 02325
VCID: 0201BB6B0E14303

1 Fault Found:
01550 - Signal for Reverse Gear
27-10 - Implausible Signal - Intermittent

End ---------------------------------------------------------------------

 

Her problems have nothing to do with the catalytic converter. If she lost power steering and the battery light came on, sounds like the serpentine belt broke. Be careful, don't run the car, it can result in timing belt issues if pieces of the belt get wedged interest wrong places.

DON'T START THE CAR.

 

Thanks buddy, that's what I thought at the roadside, and so had it towed home, but the serpentine belt is fine. I think they (battery light/PAS reduction) were just symptoms of the car starting to cut out (I wasn't in the car, my GF described that to me). I'm think either fuel pump or filter now. Serp belt is fine. Car will start and run for a few seconds then stall.

 

Squirrel in the intake system? Potatoes in the tailpipe?

 

Go to the vagcom Ross-tech wiki and you can enter your codes and get possible fixes to them.
Sounds to me like your air inlet hose to the throttle body is not sealed correctly causing a vacuum leak - I had a similar prob when I forgot to tighten it down and it popped off.

 

Ok, so having traced voltage as far as the multi-plug on the fuel pump, I just went for it and ordered, and fitted, a new (Airtek) pump, using the EPIC tech article by Robert Gedeon on AW here: https://www.audiworld.com/tech/eng95.shtml.

One of the best tech articles I've used. Car started right up after maybe 3-5 seconds cranking. Only additions to the article I would make are:
1) Wear safety glasses, as petrol (yes, it's not a gas, it's a liquid...) may spray when you release the hoses, like it did on me, and
2) my pump came with the return line fitted already and with the quick release on the other end, that I wasn't going to F*** with, so I removed that hose and reattached the existing return line to the new pump. Oh yeah, and
3) reconnect the battery -ve terminal, I forgot and couldn't work out why nothing was working for a second there... LOL

K9

 

Only problem here is what caused the fuel pump to fail and is that problem resolved?
Yes, a new fuel pump might work for awhile, but as a minimum you should change out the fuel filter.

 

FYI, loosing power steering and alternator light are the symptoms when any engine stalls out. Most see it as something to look into, when it's a symptom, not part of a problem.

The fuel pump was most likely worn out on a car this old . I would suggest getting a new fuel filter also.

Also, there was newer ECM software for the catalyst efficiency fault. The original software would falsely detect lower efficiency due to a threshold value set too low.

 

Disagree...fuel pump failures relatively rare on this young of a car...although K9COP didn't post how many miles were on the car.
BMW high pressure fuel pumps excepted, of course.

About all the guy had was that the engine stopped...