A6 2.0 tdi Misfire

[garya6]

Hi I have an Audi A6 2.0 tdi 2006, just recently it has developed a misfire. I took it to a diesel specialist who said i had fault codes on the injector loom, which is located under the rocker cover. I changed the loom took it back and he cleared the codes, but misfire was still present with no codes showing.
The misfire is getting steadily worse it seems to be on tick over ,up to 1600rpm it seems to disappear, when holding at 1600rpm it is always misfiring but as you increase rpm 1800+ it disappears and comes back around 3200rpm
I have done all the basics eg. fuel filter / air filter but no difference and like i said no codes showing up.
When i had the codes read he used a snap on solas machine which also read the injectors pressure, he pointed out that three injectors were minus and one was reading +128 this was number 2 injector, he said that the nearer to zero the injector reads the better it is , so in his opinion i need to change number 2 injector. I didnt get a feeling of confidence from him which worried me slightly first the loom then an injector, what next ?


Can anyone help?

 

[garya6]

I changed no.2 injector but car was running rough on tick over so i was advised to change the other 3 which i have now done, The car ticks over ok now but there is still a misfire at 1600 and 3200 rpm only slight though. Does anybody have any idea what the problem could be?

 

[charlie_kerr]

Had a recent similar problem, tracked down to a hole in the intercooler, are you getting smoke in the exhaust when misfiring?

New intercoller £330 fitted, problem solved.

 

[garya6]

Ok thanks for that, I have noticed today that when the car started it was lumpy until i pressed the accelerator then it smoked slightly and cleared.
It doesnt seem to be smoking otherwise.
The misfire is hardly noticeable when driving, unless i'm in a low gear then i feel it at 1600rpm. I will check the intercooler though at least i have somewhere to start, thanks i will let you know.

 

[mystro]

I didnt get a feeling of confidence from him which worried me slightly first the loom then an injector, what next ?


Can anyone help?

We don't rate the Diesel A6..we get the 3.0TDI in the Q7 which makes zero sense to me but to get to your query...find a real Audi Diesel Tech you feel comfortable with..I'll bet he'll know exactly why it's missing at certain RPM's. Seems like almost everyone accross the pond here has Diesel Pick up's..it's the same trick here--- finding the right shop or they'll screw ya like a virgin...oops sorry.

 

[garya6]

It was the fly wheel, i changed the clutch and fly wheel and its as good as new