Audi 2.5 tdi loss of power

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Sat 11 Nov 2006 20:19
Audi 2.5 tdi loss of power - gasoil
My mates A6 2.5 tdi has lost power! but only below 2000 rpm, the MAF has been changed so it is not that, is there any other common problems with this engine it is the 180bhp version. It is not a misfire just no torque below 2000 rpm used to pull well from 1100rmp. Thanks for any help.
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Sat 11 Nov 2006 20:31
Audi 2.5 tdi loss of power - Hamsafar
When the power picks up, do you get a puff of smoke?
I suspect the EGR valve is stuck open, this is what happened to mine, can you take the cover off the top of the engine, and remove the rubber vacuum hose to the EGR and plug the hole. Even if this helps, it could be the vacuum solenoid that controls the EGR by modulating the amount of vacuum. The reason a MAF can be suspected is that when a signal is sent to the EGR to open, the ECU looks for a corresponding drop in the MAF reading because of the exhaust gases substituting some of the air.

www.honestjohn.co.uk/forum/post/index.htm?t=42233

is my original thread and you can see who helped me...
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Sun 12 Nov 2006 16:33
Audi 2.5 tdi loss of power - gasoil
Has nobody else got any info on this engine? It is in an allroad if it makes any difference.
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Mon 13 Nov 2006 19:11
Audi 2.5 tdi loss of power - gasoil
Off to Audi tomorrow! I thought there would be more TDi experts out there!
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Tue 14 Nov 2006 08:39
Audi 2.5 tdi loss of power - adverse camber
Well what do you expect?
you have given really minimal description of the car and the problem.

You have received advice that the maf and egr are the most likely culprits - which is true - and pointed to a recent thread where a similar problem was discussed.

You have not given any more info or details about the vehicle age or miles or useage, slip in as a late fact that its an allroad (but is that the haldex or torsen?) manual or auto? any recent work carried out ? t/belt etc ?

There are lots of threads about tdi problems here - have you used the search function ? If you had you would see the info to check maf and egr and get the fault codes read.

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Tue 14 Nov 2006 10:07
Audi 2.5 tdi loss of power - Hamsafar
Gasoil, you didn't give enough details, we asked you questions that you couldn't be bothered to answer and probably gave the cause and you go off in a huff, what a waste of time.
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Fri 17 Nov 2006 22:02
Audi 2.5 tdi loss of power - obei79
My mate also drives a A6 2.5 tdi which suffered the same problem about a year ago ... he went to audi and they replaced the air flow sensor with a re-con one ... they recon it was a common problem .. it cost him about £150 all in and it went like a rocket after ...
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Sat 18 Nov 2006 21:40
Audi 2.5 tdi loss of power - gasoil
Thanks for your reply, Sounds like the MAF he has already changed. He had the car in at audi and they found nothing! They said now they want to start changing parts to find whats wrong. Anybody ever heard of premature camshaft failure on these engines?
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