Hi all,
I'm considering buying a mates 2004 A3 2.0 Tdi which has only done 65k. However, after he's been driving it for an hour or so it developes a slight misfire if it's in a higher gear than 2nd at low revs. Apart from this it's fine and drives very well. What I'm wondering is, could this be anything serious and expensive to fix like an injector or something?
Any ideas guys? Thanks in advance.
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For a drivability fault like that; the best first step is to get the latest level software downloaded into the ECU be the dealer.
Might be injector wiring; it depends on how long it's been doing it.
Don't overspend on it; the 2.0ltr is not as tough as the 1.9PD that preceded it.
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Hi there
I am by no means an expert on this but ... I was just going to put a message out on this very subject and saw your post.
I have the same car (audi TDI 2l S) which has done less than 60,000 miles with the same problem only being a girl didn't investigate further - the car now won't start at all and I have just been told the diognostics machine is saying there is a fault with the No 4 Injector and I am now looking at a rather costly bill - if that fixes it!!
Of course it out of warrenty but I am really shocked that a fault on a car of its age and milage has developed such a serious fault. I have been told it is probably 'dirty fuel' rather than ware and tear..
Could it potentially be a problem with audi? I have been quoted £250 for the part by my specialist garage - which I trust but its cheaper than other prices - could this be a re-conditioned part, if so should I avoid it????
I was really worried when buying my audi of the potential expense of the EMS - I love my beautiful audi but can't afford another bill like this :(
Sorry for long post ....
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nvh
I've yet to see a faulty injector cause a non-start fault on one of these. Unless you've been putting something other than pump diesel in the tank [have you?] then the standard filtration system will preclude "dirty fuel" being a problem.
What tests have they done to find the real cause of the problem and how experienced on these diesels are they?
At £250, that does sound like a cleaned-up second-hand injector - not recommended.
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Thanks for reply - although it means my bill may be higher...
I have only ever put pump diesel in this vehicle - honest! It is my pride and joy!
I avoided taking it to audi dealership as I thought they would rip me off.. The garage I have relayed my car to is a VW and Audi specialist who has been in operation since 1981 - thats all I know.. I think all they have done is connected it up to the diognostics machine - he didn't touch it in case it was still under warrenty.
I have called the garage that I purchased the vehicle from and all they are willing to do is repair the fault for a good price (or so they say). The problem is I have to pay for relay again and the cost of the diognostics machine - I could well spend £200 before they even start.
Really don't know what to do - can you recommend anyone in the Exeter area?
nvh
Edited by Dynamic Dave on 02/07/2008 at 19:52
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nvh
I think you first step is to establish exactly what the problem is. Until then; everything is conjecture.
Do you know which code was found? What was it doing before it finally stopped and did it cut-out, or fail to start from hot/cold?
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Hi
The code is 16688 - number 4 misfire detected. I asked whether the pice for the part was new or re-conditioned - he said new.
I have noticed over the last 6 months that the car was misfiring only when I accelerate from memory.
The car had been parked for a week - when I went to get in it yesterday the engine turned over but just didn't start and then the oil pressure warning light came on in the central display (red).
Before I was away on holiday the oil warning light (yellow) came on - at the time I was in the middle of cornwall and I thought the car would take the same oil as my friend's VW van (long service life semi synthetic) so I put some of that in just for my trip back to Exeter.
Yesterday I checked the oil and it was low so I have now half filled it to see if that rectified the problem but it didn't.
nvh
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nvh
Those newly-revealed facts puts a completely different perspective on it. Forget injectors; there's nothing in that code to justify the cost of replacing one - or to explain a non-start. [Ignore an oil pressure light if the engine isn't running.] What do the garage say is the reason for it not starting?
Far more worrying is the fact that the oil level has been neglected. That could have caused catastrophic damage to all sorts of areas, like the cam-followers.
These do need the right oil; but any oil is better than none in the short term.
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That is the reason they are giving for the nonstart - but to be honest I was wary in case it didn't fix it - I did tell him the full storey of the oil etc..
I have also tried to jump leads to start it.. didn't work.
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I cannot see how a generic misfire code equates to a non-start - unless there's a lot more yet to be revealed.
Is the tank pump even running at key-on? There are many reasons for a non-start - and a failed injector isn't one of them.
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SL
Thats all the information I have - however, there was a fault with the engine managment system previously but as it was covered under the warrenty I do not gave the paperwork - I really must pay more attention! I will get the details tomorrow.
I'm sorry I don't understand tank pump running :(.
Is it possible then that I have a fault with the injector and something else which is causing the nonstart.
nvh
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nvh
There is no evidence presented to confirm an injector problem. A vague misfire code could be caused by almost anything; but is not related to the non-start fault.
There is a low-pressure fuel pump inside the fuel tank; it runs for about five seconds when you turn the key on. If that isn't running, then nothing will work. Your garage should stop fixating on a nonsense code and get down to checking the basics required to get it started.
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Okay thanks - I will suggest that they look at alternative causes before going down that route.
The local mechanic who tried to jump start the car did say that it didn't sound like there was any fuel getting to the engine - maybe I will go back to the garage that serviced my previous car - if they arn't willing to help.
If I find out I will let know....
n v h
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Just to let you know - loose connection found on the injector that was all. There was also a problem with the internal light so suspected drain on the battery. Although I did try jump starting the car initially and din't work.
Anyway - appears to be fixed now for a grand total of 3 hours labour so not as bad as initially thought.
Thanks for help
nvh
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nvh
Thanks for the outcome - I still can't quite get it all to gel; but it's a very hot and sticky day.....
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The PD diesels are prone to intermittent bad connections to the plugs on the injectors which will give rise to a misfire and which doesn't always set a fault code. The wiring runs inside the cylinder head in a plastic guide tray and terminates in a multi-way connector on the "back" of the cylinder head under the tandem pump.
VAG don't use military quality connectors for this application and the specified cable is, in my view marginal for life due to embrittlement in hot engine oil.
Military diesel engines with internal cabling have given trouble even with PTFE wire and M-S syle connectors so the commercial standard components specified by VAG are clearly at risk. This aspect of the design is a downside of the PD but the principle has considerable advantages in other areas, particularly in its ability to handle fuel of low lubricity. (But not fuels of either high viscosity or high density - so no straight veg oil).
Luckily the fix on the PD is fairly cheap and easy to accomplish - if you can get a diagnosis.
659.
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659
Like myself; you'll have seen numerous injector-loom failures - but have you ever seen a non-start from it? That's the bit I can't get my head round.
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Screwloose, I would agree. I have only ever seen a bad loom cause a misfire - sometimes only when hot. Starting is not usually an issue.
659.
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