A6 2.5 TDI feels flat
Author
Discussion

parson0j

Original Poster:

23 posts

292 months

Wednesday 10th October 2007
quotequote all
Hi - I run a 99 2.5 TDI A6 Avant with 90k on clock. When I bought it, cambelt was done (at 80k) amongst other little niggles. Whilst it is a lugger, I would have expected some turbo but nothing - feels as flat as a pancake up the rev range. Rolling road last week showed 120 bhp (instead of 150) and 230Nm of torque (instead of 310). Had the turbo pressure checked, the airflow meter replaced a month ago and other diagnostics showed all OK.

So what to do? Any thoughts appreciated.

Thanks

RS4john

331 posts

239 months

Wednesday 10th October 2007
quotequote all
Interesting that, we had a 2.5TDI avant, BEFORE the timing belt was changed it ran strongly, after it ran like a dog, who did the belt? was it main agent or someone else?.
We ended up PXing it as it never ran the same again,the belt was done by an indenpendant and consequently was done wrongly. The main agent took it in and we spend money on it, but it never ran as strongly again. mad

nail_it

968 posts

238 months

Wednesday 10th October 2007
quotequote all
OK, been through this problem.
Had cambelt changed by main dealer on an A4 TDi & it also ran flat.
Vehicle was 5 years old with 55,000 on the clock frown

One problem was they had seriously overfilled it with oil.
Got no joy from the dealer ......no surprise there mad
So I did this which is advisable on TDi engines:
Using solvent or a detergent clean the egr, intake & bottom boost hose.
The crud that deposits around the egr can take some shifting!
Leave the components to completely dry overnight, before re-assembling.
Check for leaks & use new clips to ensure a sealed job.

Guarantee the car will spank biggrin

Then I took the bill to the main dealer & got them to pay the money.
Plus, extra for my troubles hehe

phumy

5,828 posts

267 months

Thursday 11th October 2007
quotequote all
nail_it said:
OK, been through this problem.
Had cambelt changed by main dealer on an A4 TDi & it also ran flat.
Vehicle was 5 years old with 55,000 on the clock frown

One problem was they had seriously overfilled it with oil.
Got no joy from the dealer ......no surprise there mad
So I did this which is advisable on TDi engines:
Using solvent or a detergent clean the egr, intake & bottom boost hose.
The crud that deposits around the egr can take some shifting!
Leave the components to completely dry overnight, before re-assembling.
Check for leaks & use new clips to ensure a sealed job.

Guarantee the car will spank biggrin

Then I took the bill to the main dealer & got them to pay the money.
Plus, extra for my troubles hehe
I dont understand why the dealer should give you money for you to clean the boost hoses out and the egr! They would have done that, had you asked them to, but if you decide to go do it yourself, then there is no onus in them to pay you. These things get clogged up over a period of time anyway and its down to you.

Its like you going to get the tyres changed, then going back to the dealer saying, " there you go, you owe me for the tyres ive just fitted". Sorry i can not see that happening, unless of course i have missed the point completely

RS4john

331 posts

239 months

Thursday 11th October 2007
quotequote all
The one we had with a problem ( after belt fitting) had the fuel pump overhauled!!!! still no go, I think the Main agent ran out of ideas.
We had to out it, shame really.vomit

philip walker

113 posts

248 months

Thursday 11th October 2007
quotequote all
If there are no fault codes stored and you have changed the maf. I would get the pump timing checked, this can be done via Vag-Com.
Some Garages still time tdi engines up using the blob of paint method, it does not work correctly. They should use the correct pins and plates.

parson0j

Original Poster:

23 posts

292 months

Thursday 11th October 2007
quotequote all
Thanks for all the replies. Independent VAG guys did cambelt and it seems OK. I went back this a.m to see them and they replaced the air filter and coolant guague that was showing off readings. Runs OK but still well short of where it should. Pump timing OK and all else as far as can be seen. Will investigate cat and ERG next I think. Baffling!

Dr G

15,983 posts

272 months

Thursday 11th October 2007
quotequote all
Exactly, it 'seems' OK - you would be amazed with the difference that half a tooth can make.

Different kettle of fish but my Golf had been running 16.5 standing quarters. A tooth on the timing belt (tensioner was throwing the marks out) and a play with the ignition and I get 15.5s. Utterly, utterly different car to drive.

philip walker

113 posts

248 months

Thursday 11th October 2007
quotequote all
parson0j said:
Thanks for all the replies. Independent VAG guys did cambelt and it seems OK. I went back this a.m to see them and they replaced the air filter and coolant guague that was showing off readings. Runs OK but still well short of where it should. Pump timing OK and all else as far as can be seen. Will investigate cat and ERG next I think. Baffling!
How did they check the pump timing?

tdi rs

5 posts

226 months

Wednesday 19th December 2007
quotequote all
Id take it to a garage that understands tdi engines.They would be able to sort it.It sounds like a turbo issue to me partially siezed actuator or dodgy boost controller.

agent006

12,058 posts

294 months

Thursday 20th December 2007
quotequote all
phumy said:
of course i have missed the point completely
Dealer overfilled the oil, hence causing the problem. Wouldn't do anything to sort it themselves. paid the bill for DIY repair though.

phumy

5,828 posts

267 months

Thursday 20th December 2007
quotequote all
agent006 said:
phumy said:
unless, of course i have missed the point completely
Dealer overfilled the oil, hence causing the problem. Wouldn't do anything to sort it themselves. paid the bill for DIY repair though.
EFA

phumy

5,828 posts

267 months

Thursday 20th December 2007
quotequote all
phumy said:
agent006 said:
phumy said:
unless, of course i have missed the point completely
Dealer overfilled the oil, hence causing the problem. Wouldn't do anything to sort it themselves. paid the bill for DIY repair though.
EFA
Plus i still dont see why the dealer should pay for cleaning crud from the boost hoses, as all tdi cars accumulate that over time. EGRs get crudded up over a period of time too so its not something that just occurs over night or instantaneously either.