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  #1  
Old 13th November 2018, 06:11 PM
erubus erubus is offline
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Default 4.2TDi sudden death

Hi guys, haven't posted for a while as the car has been behaving admirably.

Was driving to work this morning, following a geriatric doing 35 mph. I overtook, didnt boot it, just accelerated to 65ish then pulled back in. The car started to slow down despite the throttle position staying constant. It continued slowing down till it reached about 40 mph, at which point my foot was in full kickdown position, at this point the coil light started flashing and the car continued to slow.

There was a road end, so I turned in. I was doing 10 - 15mph into the road end and the car wouldnt accelerate. Foot buried in the carpet it was managing to stay at 15mph, with the engine misfiring terribly. sounded like it was only running on a couple of cylinders. I pulled into a field and put it in park. Foot to the floor it would only do 2'000 rpm and was rough as a badger's arse. I switched it off for a minute or two to see if it would clear bt it wouldn't start again and hasn't since.

I got the OH to bring the laptop in on the way to work so I could scan it (and get a lift to work myself!) I got these faults:


005715 - Please check DTC Memory of ABS Controller
P1653 - 002 - - Intermittent
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 360955 km
Time Indication: 0
Date: 2018.09.05
Time: 06:59:15

012295 - Camshaft Position Sensor (G40)
P3007 - 001 - No Signal
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 360955 km
Time Indication: 0
Date: 2018.09.05
Time: 06:59:15

004104 - Mass Air Flow Sensor 1/2
P1008 - 000 - Implausible Signal
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 360955 km
Time Indication: 0
Date: 2018.09.05
Time: 06:59:15

000257 - Mass Air Flow Sensor (G70)
P0101 - 001 - Implausible Signal
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 364983 km
Time Indication: 0
Date: 2018.11.13
Time: 07:09:12

Freeze Frame:
RPM: 1386 /min
Torque: 3.9 Nm
Absolute Pres.: 1009.8 mbar
Temperature: 10.8°C
(no units): 92.0
(no units): 92.0
(no units): 92.0

000565 - Boost Pressure
P0235 - 001 - Regulation Range not Reached
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 364983 km
Time Indication: 0
Date: 2018.11.13
Time: 07:09:25

Freeze Frame:
RPM: 2772 /min
Torque: 483.6 Nm
Speed: 80.2 km/h
Absolute Pres.: 2458.2 mbar
Absolute Pres.: 1448.4 mbar
Mass Air / Rev.: 1010.5 mg/str
Mass Air / Rev.: 1010.5 mg/str

004455 - Mass Air Flow Sensor 2 (G246)
P1167 - 002 - Implausible Signal
Freeze Frame:
Fault Status: 01110010
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 364983 km
Time Indication: 0
Date: 2018.11.13
Time: 07:09:41

Freeze Frame:
RPM: 1134 /min
Torque: 3.9 Nm
Absolute Pres.: 1009.8 mbar
Temperature: 19.8°C
(no units): 72.0
(no units): 96.0
(no units): 96.0

000565 - Boost Pressure
P0235 - 001 - Regulation Range not Reached
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 364983 km
Time Indication: 0
Date: 2018.11.13
Time: 07:09:25

Freeze Frame:
RPM: 2772 /min
Torque: 483.6 Nm
Speed: 80.2 km/h
Absolute Pres.: 2458.2 mbar
Absolute Pres.: 1448.4 mbar
Mass Air / Rev.: 1010.5 mg/str
Mass Air / Rev.: 1010.5 mg/str

My guess is that the MAF faults and the boost pressure faults are spurious and related to me having my foot to the floor and having no power.

The Cam sensor one is interesting though as it is a "no signal" fault which suggests a compete failure of the sensor or wiring to my mind.

My thinking so far is either total failure of the cam sensor G40 or total blockage of the fuel filter (a glob of diesel bug maybe). Both parts are cheap enough that I'm happy to chuck the parts at it in the hope that one or both is the problem.

I'm a big chunk of money down already due to being loss of earnings and recovery costs! Has anyone got any ideas based on the above. Ideas on further tests to figure out the problem also greatly appreciated. I'm a bit limited on what live data I can get due to it not starting. Had to sort the old Landy out so i can use that for work, but its not exactly a commuting vehicle so the sooner I can get back to 300+ bhp and comfort from 53bhp and agricultural the better!

gill
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  #2  
Old 13th November 2018, 06:13 PM
erubus erubus is offline
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PS: I havent the foggiest idea why there is an ABS fault stored in "Engine 1" but I included it anyway.
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Daily drive: 2008 A8 4.2TDi
2003 A8 4.0TDi. 4 zone climate, double glazing, Bose - dead
Other cars: 1980 Land Rover Series 3, 2.25d, hydraulic winch,Van/station wagon/topless depending on my mood
1990 Land Rover 90 factory county station wagon with all the luxury additions, such as a clock and a tape player.
2007 A4 3.0TDi s-line cabriolet quattro
2000 A8 D2 2.8 quattro, looking for a new home - gone
2003 A6 3.0 quattro, in the way... anyone want any parts? - gone
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  #3  
Old 13th November 2018, 06:28 PM
snapdragon snapdragon is offline
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The ABS does register a fault in the Engine module if it has one stored.
The first three errors look historic (4000km ago)


07:09:12 G70 got implausible signal @1400rpm
07:09:25 Boost pressure not in range @2800rpm
07:09:41 G246 MAF 2 implausible signal @1134rpm

So on a timeline, the codes are appearing within in a 29 second window.
Hopefully just a boost pipe blew off on whichever bank gave the first code from G70 I would check everything from the turbos' outlets to the inlet manifold.?

Looking at SSP PDF for the 4.2tdi G246 and G70 are are the MAFs?
EDIT #59 here...
http://forum.a8parts.co.uk/showthread.php?t=9347

Last edited by snapdragon; 13th November 2018 at 06:54 PM.
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  #4  
Old 13th November 2018, 06:33 PM
HPsauce HPsauce is offline
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The MAF sensor errors seem to be the latest ones and are today.
Odd that both sensors show an error, suggesting another factor such as a leak?

The others are from some months ago so probably not very relevant.

Always good practice, if you have ready access to VCDS, to scan codes regularly, note them and clear. Then review at subsequent scans.
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Last edited by HPsauce; 13th November 2018 at 06:36 PM.
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  #5  
Old 13th November 2018, 06:50 PM
erubus erubus is offline
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I hadnt noticed the dates, duh! Mind you my laptop makes up the time and date - it currently thinks its 2344 on 11/11/18.

I cleared the codes and they all came straight back after the next starting attempt. I'll have another go at it tomorrow. Clear all the codes then try another scan. This car doesn't like getting plugged in and occasionally has a total meltdown like it has drained the battery in a couple of seconds.

Re: air leaks, i would expect clouds of black smoke and noise in that situation along with the lack of power. Generally wouldnt expect the rough running - at least in the times a pipe has burst on any of my other audis.
__________________
Daily drive: 2008 A8 4.2TDi
2003 A8 4.0TDi. 4 zone climate, double glazing, Bose - dead
Other cars: 1980 Land Rover Series 3, 2.25d, hydraulic winch,Van/station wagon/topless depending on my mood
1990 Land Rover 90 factory county station wagon with all the luxury additions, such as a clock and a tape player.
2007 A4 3.0TDi s-line cabriolet quattro
2000 A8 D2 2.8 quattro, looking for a new home - gone
2003 A6 3.0 quattro, in the way... anyone want any parts? - gone
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  #6  
Old 13th November 2018, 06:57 PM
erubus erubus is offline
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Quote:
Originally Posted by snapdragon View Post
The ABS does register a fault in the Engine module.
The first three errors look historic (4000km ago)
Why is the 000565 code repeated twice?
Is because there are two engine ECU's - one for each bank or a typo?

07:09:12 G70 got implausible signal @1400rpm
07:09:25 Boost pressure not in range @2800rpm
07:09:41 G246 MAF 2 implausible signal @1134rpm

So on a timeline, the codes are appearing within in a 29 second window.
Hopefully just a boost pipe blew off I would check everything from the turbos' outlets to the inlet manifold.?

Can you get the SSP PDF for the 4.2tdi and identify what G246 and G70 are?
EDIT #59 here...
http://forum.a8parts.co.uk/showthread.php?t=9347
I didnt see this post on first read through. That does seem like a logical conclusion to reach from the data. Id still have expected loads of smoke and noise from past experience but they are easy things to check so it makes sense to go over the easy stuff first.
__________________
Daily drive: 2008 A8 4.2TDi
2003 A8 4.0TDi. 4 zone climate, double glazing, Bose - dead
Other cars: 1980 Land Rover Series 3, 2.25d, hydraulic winch,Van/station wagon/topless depending on my mood
1990 Land Rover 90 factory county station wagon with all the luxury additions, such as a clock and a tape player.
2007 A4 3.0TDi s-line cabriolet quattro
2000 A8 D2 2.8 quattro, looking for a new home - gone
2003 A6 3.0 quattro, in the way... anyone want any parts? - gone
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  #7  
Old 13th November 2018, 07:03 PM
snapdragon snapdragon is offline
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Sorry I did edit as I changed my mind.
I guess if both MAFs are giving very different readings they will both get an implausible signal code of some sort.

However, what happens if you try to start? Does it just crank. I wouldn't expect a boost leak or faulty MAF, turbo etc to stop it starting, I don't think you even get any kind of airflow or pressure readings during cranking and they are just assumed.

What about the airflow throttle things maybe one has shut or broken off inside blocking the intake?
Maybe if you crank over the engine and get someone to compare the exhausts and see if they puff air equally?
Does it sound normal when cranking? No abnormal mechanical noises?

Last edited by snapdragon; 13th November 2018 at 07:06 PM.
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  #8  
Old 14th November 2018, 09:02 AM
erubus erubus is offline
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Yeah, the engine just cranks over. It was having a bit of a farty thing going on with its first turn or so, almost a misfire. That was with the battery getting low though. Fresh battery was spinning it over fine and sounded normal.

When I've had boost leaks before on other Audi tdis they've all started and run just fine. It's only when you ask for power that you realise something is up.. no power and thick clouds of smoke until you get an underboost fault come up with the engine management light coming one. It's always been accompanied with a whooshing noise with all the air escaping.

This fault was just a lack of power, coil light (emission control?) Not the engine light, then really rough running as if on hardly any cylinders.

Swirl flap could be an issue... I really hope not. That's likely a destroyed engine if it is. Is there any way of checking that without dismantling?
__________________
Daily drive: 2008 A8 4.2TDi
2003 A8 4.0TDi. 4 zone climate, double glazing, Bose - dead
Other cars: 1980 Land Rover Series 3, 2.25d, hydraulic winch,Van/station wagon/topless depending on my mood
1990 Land Rover 90 factory county station wagon with all the luxury additions, such as a clock and a tape player.
2007 A4 3.0TDi s-line cabriolet quattro
2000 A8 D2 2.8 quattro, looking for a new home - gone
2003 A6 3.0 quattro, in the way... anyone want any parts? - gone
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  #9  
Old 14th November 2018, 07:25 PM
erubus erubus is offline
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Scanned the car again tonight after work and got this:


012295 - Camshaft Position Sensor (G40)
P3007 - 001 - No Signal
Freeze Frame:
Fault Status: 01110001
Fault Priority: 0
Fault Frequency: 5
Reset counter: 255
Mileage: 364983 km
Time Indication: 0
Date: 2018.11.13
Time: 08:19:29

Freeze Frame:
RPM: 147 /min
Torque: 27.3 Nm
Speed: 0.0 km/h
(no units): 32.0
Voltage: 8.51 V
(no units): 193.2
(no units): 338.8

I also got the ABS fault again and the usuall glow plug faults (6 of them are open circuit)

The time and date are suspect again but will be from yesterday as it was definitely cleared. I tried starting the car, but as it often does when youtry to start it when its connected to vcds it had a total meltdown and flattened the battery in seconds after managing about half a turn of the engine. Tried again with another battery and it did the same thing.

I'm going to get a cam sensor for it. For the money I've nothing to lose really. might work, might not. I had a quick look for burst pipes but (A) its damn near impossible to see any and (B) I was starving!
__________________
Daily drive: 2008 A8 4.2TDi
2003 A8 4.0TDi. 4 zone climate, double glazing, Bose - dead
Other cars: 1980 Land Rover Series 3, 2.25d, hydraulic winch,Van/station wagon/topless depending on my mood
1990 Land Rover 90 factory county station wagon with all the luxury additions, such as a clock and a tape player.
2007 A4 3.0TDi s-line cabriolet quattro
2000 A8 D2 2.8 quattro, looking for a new home - gone
2003 A6 3.0 quattro, in the way... anyone want any parts? - gone
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  #10  
Old 14th November 2018, 09:15 PM
snapdragon snapdragon is offline
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Oh brilliant - fingers crossed.
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