hi guys

i own a 2000 a6 avant 1.8T which has devoloped a misfiring fault. it generally drives on average at 30mph max with my foot to the floor with intermittent bursts of power that last no more than a couple of seconds.

can anyone help me in locating the problem, i can't afford to give it to audi so will try and replace the relevant parts myself once i know what is causing the problem.....

i've had suggestions of the maf filter or coil packs that could be causing this but these were suggested before i done the scan... i was able to arrange a vag-com scan today and this is what come back........

vag com - faults found......

17544 - Fuel Trim: bank 1 (add) system too rich - P1136

17536 - Fuel Trim: bank 1 (mult) system too lean - P1128

16684 - random/multiple cylinder misfirwe detected - P0300

16685 - cylinder 1 misfire detected - P0301

16687 - cylinder 3 misfire detected - P0303

16688 - cylinder 4 misfire detected - P0304

16686 - cylinder 2 misfire detected - P0302

17925 - main relay (j271) electrical malfunction - P1517

18010 - Power Supply Terminal 30: voltage too low - P1602

18034 - Power train Data Bus: missing message from TCU - P1626

17834 - EVAP Purge Valve (n80) open circuit - P1426



i called audi with the details of the main relay fault (17925 - main relay (j271) electrical malfunction - P1517) i thought that replacing this would be as good a place to start but after calling 3 dealers nobody could tell me what relay this is! anyone out there know????

thanks

the relay is under the hood there are 3 relays and 6 fuses 2 ate the top and the other 4 at the bottom relay 3 is your counting from left to right, I also agree this is probably the problem for all the other codes as I have checked through my data

wow that reply was quick! thanks!!!!!

i will be so happy if a relay replacement sorts this, i've just been told it could be the ecu!

where abouts under the hood on a 1.8t should i be looking for the relay?
there is nothing obvious when i lift the hood?

thanks

left hand drive its passenger side below the windshield

there are 3 configurations the plate has for different models all the relays for the engine side is the right hand side of the plate

my a6 is right hand drive (i'm in the UK!)

i still can't see nothing obvious near the windshield! could it be in the same box as the ecu?
i have read somewhere that it is possible vag-com can find this relay in an engine that may not even be in that model of car, could this be the case?

i tried to copy and paste a picture of my engine bay on the forum for a guide but was unable to.
thanks again for the amazingly quick response!!!!!!

its to the left of the battery near the inner wing driver side for the UK

my battery is nearer the centre of the car but towards the passenger side,
on the drivers side nearest the inner wing is the ecu box

well its got to be in there mate

as soon as it stops raining i'm out there with my toolbox!
i'll post up what i find, hopefully 3 relays and 6 fuses...........

thanks for your help