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View Full Version : a6 1.8t power problems and cutting out



mark1holman
29-01-2007, 12:08 PM
Hi i am new to the forum so please bear with me!!
my car:
audi a6 avant 1.8t
year 2000
milage wopping 158,000

in dec 06 i had 2 lamder sensors and the mass air flow meter replaced. the car the developed an intermittant problem which resulted in the car cutting out mostly when slowing to a stop. then within a few days i noticed in 2nd gear the car was very unfesponsive but once it got going was no problem.

audi did a diagnostic test and wanted to strip down the turbo but after discussing the problems with the technition i decided to have a local garage replace the turbo, oil feed pipe and the vaccum pipes attached to the turbo. this has all been carried out along with a new dump valve but the symtoms are still there:(

when the car is cold i try to accelarate but there is no power the rev counter is stuck at 800 revs, once on the move the car is holding back between 200 - 3000 reves but above this it feels fine and when i come to slow down/ stop the car cuts out. when i restart the car the revs jump from 300-1300 revs or cuts straight out. however when the car is warm (about 10-15 mins of driving) it runs perfect ticks over at 800 revs and when pulling away does not seem to have power loss.

i spoke to the garage that replaced the air flow meter and they said it was not an audi one but was not a bosch either, could this be due to the air flow meter? i have read numerous postings and they keep mentioning the MAF.

i should also add the VAG picked up 4 faults:

1. Pressure drop between turbo and throttle valve. (check dump valve)
2.fuel tank bank 1 (multi) system to rich
3.oxygen(lambda)sensor heating B1 S1 performance too low
4.fuel trim bank1 (add) system too rich

this was done by a mobile tuning guy my friend knows but he said 1st fault would cause other 3 faults so it is this one most significant but as Dump valve been replaced he wants me to take it to audi

any advice would be appreciated as i do not want to spend much more on car total so far £1350:zx11: :zx11:
many thanks

mark

mullij1
31-01-2007, 03:34 PM
Hi Mark, I'm not sure if this is related but might help. Did you have the ECU checked out? I currently have a 2001 A6 but my last car was 1996 A4 1.8t. It completely cut out on me on a dual carriageway and simply would not start again. Two separate mechanics looked at it and reckoned it was the fuel pump. I had that replaced and no joy. Then it was suggested that i reset the ECU. So i disconnected it for and hour or so and once i put it back everything was fine. Your problem sounds more complex but you can sometimes focus too much on one line of investigation.

Jim

mark1holman
31-01-2007, 03:38 PM
hi jim

thankx for reply, i will get audi to do this when it goes in.

i am getting the MAF replaced on friday as the audi garage road tested it with the MAF disconnected and although the cutting out continued the car was running perfect. the mechanic said that the MAF is also likely the culprit for cutting out.

watch this space friday!!!

cheers mark