A6 3.0 TDi Smoking at Idle - Injector Failure?

[BDriver]

I have an 05 plate A6 3.0 TDi Quattro, which I have owned for 1 year. It now has 70k miles on the clock and it has started to smoke badly in slow traffic and at idle. Audi tell me all 6 injectors have failed and it will cost me £2.5k to replace them. After complaining that all 6 could not have failed at once Audi UK have offered to pay 20% of the cost. Does anyone have any experience of such a fault happening with any other cars?

[a8 tech]

All the injectors must be encode to the engine control unit for fuelling calibration so if defective due to mechanical wear/leaking then a full set would be the suggested repair within warranty so why not outside of warranty.

The actual fault

Mechanical wear of the needle attachment of the injector leads to an increased fuel injection into the combustion chamber. The fuel is not completely burnt, which causes white smoke (unburnt fuel) or juddering when the engine runs at idle speed for some time

So if you only replace the suspected injectors then its likely the others will fail shortly after

You can determine which injector is at fault by observing measured value blocks 72 to 77

http://wiki.ross-tech.com/index.php/...BKS/BMK/BUN%29

[spam-head]

Hi, i have the same problem with my 3.0ltr did the injectors solve your problem?

[BDriver]

Yes, the new injectors solved the problem. Audi UK initially offered to pay 20% of the cost but that still left me with £2k to pay. I took the car to an independant diesal injector specialists and they tested all 6 injectors and confirmed that all 6 had failed at idle/tick over. The independant garage thought it was a mechanical failure of the injectors that should definately not have occured after only 60,000 miles. I went back to Epsom Audi to get the injectors replaced and asked for the old injectors as I wanted to take the matter further. When I picked up the car the salesman told me that he had re-sent my full Audi service history to Audi UKand that they had agreed to pay nearly 90% of the costs, so perhaps the £200 I paid to have the injectors checked out independantly was worth it?! I hope you find the cause of your problem, best of luck.

[markellis]

Yup had this problem with my A6 05 3.0 tdi just had a set of Ebay injectors fitted ..... so far so good £1300 total cost including filter and long life oil change (you might notice you oil level rising as un-burnt diesel finds its way in to the sump :-(
So its worth replacing when you have the injectors done.

My local dealer offered £500 of the £3500 they quoted to replace the injectors but only if I had the car serviced by them (£403) as its last service was by an Indi. Latest faults ...Ignition switch fallen to pieces with key suck in lock £230 to investigate and strip dash and £136 for lock..... this A6 3.0 tdi Avant 2006 is starting to turn in to an expensive pit in the ground ....... Time for a review of my Audi allegiance :-( growing very unhappy!