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  #21  
Old 23rd November 2018, 08:10 PM
erubus erubus is offline
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It's not looking good. I tested the +5v and earth pins today and both tested fine. I didn't test the signal wire because I can't be sure what the story is with the injectors after disconnecting the ECU.

I stuck my endoscope down the hole the cam sensor fits into and turned the engine over. I can't see anything moving at all. To be fair I can't see much but I should definitely see something moving as a cutout in the camshaft or a raised bit would have to move in close proximity to the hall sensor for it to work. The camshafts on the other bank are turning because I can see the spur gears through the oil filler.

I suppose the next thing to try would be taking off the inlet manifold to see if I can see any of the valves moving to confirm it.

I don't understand how I can't hear anything out of the ordinary. If one of the chains had snapped you would have expected it to be rattling badly for thousands of miles before it snapped. Same or tensioner, you'd expect rattling. Even if the chain had snapped you'd expect to hear it sounding like a box of spanners.

I suppose the sprocket could have come away from the taper on the camshaft. At any rate, it looks like the engine is going to have to come out. Even if I could afford a new cylinder head, the engine will still need to come out. There really isn't any way I can take it out. I don't have the equipment to lift the car off the top. I don't really have the space and I certainly don't have the time. Getting a garage to do it is an absolute non starter. That would be thousands just in labour. I was kind of hoping the car would have lasted the three years it will take to pay for it. Think I got about 5 months.
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  #22  
Old 23rd November 2018, 08:31 PM
MikkiJayne MikkiJayne is offline
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I'm not sure we are talking about the same thing here.

This is the G40 sensor removed with the trigger ring on the end of the cam. The pic is from a 1.8T, but its the same concept as the V8.



It should be simple to see the trigger ring turning, but your description of looking down a hole suggests its a completely different arrangement to this?

I'm inclined to agree it doesn't sound (literally) like a mechanical issue - if the cams on one side were stationary the engine likely wouldn't even turn over. There's no wiggle room in a diesel engine.
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Last edited by MikkiJayne; 23rd November 2018 at 08:36 PM.
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  #23  
Old 24th November 2018, 12:16 AM
erubus erubus is offline
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We're not talking about the same thing.... Well, we sort of are. The G40 on the 4.2tdi looks much the same as a crank sensor. There is a hole in the bottom rear of the left bank rocker cover that the sensor fits into. Although fairly accessible for an A8, it's still really awkward to get to and all the action is happening 3/4" down a hole that you can't see down.

Putting the endoscope down makes me fairly certain that the left bank camshafts aren't turning.
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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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  #24  
Old 24th November 2018, 09:12 AM
MikkiJayne MikkiJayne is offline
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Ah that makes more sense now. Interesting that its a hall effect sensor in that configuration. Usually those are inductive pickups, but the wiring diagram is definitely a hall sensor.

How hard is it to get the cam cover off?
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  #25  
Old 24th November 2018, 09:50 AM
erubus erubus is offline
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Getting the cam cover off will be a pain as all the injectors will have to come off first. This isn't a huge Hasse but I won't be able to turn the engine over with the cover off without getting all new seals etc. It's not something I want to be doing unless I'm 100% sure the head needs to come off. I think I'll be better taking the manifold off and eyeballing the valves first to confirm 100% then I can decide whether to fork out for a new engine/head or whether to break the car and try and make some money back.
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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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  #26  
Old 24th November 2018, 10:11 AM
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ivanhoe ivanhoe is offline
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Sorry to hear of your problems. Is the vcds mileage correct at 365000km, 226000miles?
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Last edited by ivanhoe; 24th November 2018 at 08:19 PM.
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  #27  
Old 24th November 2018, 05:37 PM
erubus erubus is offline
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No, the mileage, like the date and time, isn't correct. That's not to say it's not a high mileage car but it was a one owner car that had been religiously services at an Audi dealer. There were receipts for absolutely everything. The only job not done by Audi was the gearbox oil and filter changes every 40k. If it wasn't for that and the price, which reflected the (90% motorway) miles, plus all the extras and generally excellent condition, I wouldn't have bought it.

I've been offered a 20 year old Toyota Corolla for sweetie money until I decide what will happen with the A8. It's going to be a change. My last three cars have been 8's and I've only had Audi's for the last ten years or so except for the landys.
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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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  #28  
Old 1st December 2018, 03:36 PM
erubus erubus is offline
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Little update. I put the endoscope down the little plugged holes on top of the cam sprocket housings. On the n/s bank, you can see everything spinning away clear as day. O/s has no movement at all so definitely got a snapped chain and presumably a wrecked head.

How much do you guys think I'd make selling the car as is, 2008 excellent condition in general, gearbox oil changed at 60k intervals.

Probably make more breaking it but I don't have the time and fixing it is unlikely given the cost of parts and time involved.

Gill
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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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  #29  
Old 1st December 2018, 04:03 PM
MikkiJayne MikkiJayne is offline
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Damn
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  #30  
Old 1st December 2018, 08:55 PM
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tc4332 tc4332 is offline
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Bloody Hell.
Sad news.
Feel for you.
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