Hi all,

I have been having issues with my Audi pouring out grey (diesel smelling) smoke. So today I decided to unplug the injectors one by one to see if one of those was faulty. 

When I unplugged injector 1 or 4 the engine just ran rough, but when I unplugged injector 2 or 3 the engine just cut out. 

Any ideas why it would do this? Or if this is indicative of a problem?

Mark.

Hi Mark, my advice would be to get a diagnostic check carried out. 

Is the engine running rough or any warning lights on the dash? 

Cheers

Steve

No rough running and no error codes, just lots of smoke!

Had it into a garage a few weeks ago and they couldn't get their heads around it ether. My thoughts are ether injector fault or piston rings 😞

Mark.

The fault could be many things: injectors, rings, valves, ECU, cam position sensor. Grey smoke alone is not enough of a diagnostic tool to identify which with any certainty. A full diagnostic check at a garage is my best suggestion, unless you feel like stripping the engine.

Hello Mark, 

This problem can be typical of injector issues, and this would be my first port of call. Guess it also smells of diesel and annoys the neighbours!

If you are taking it to an ‘ordinary garage’ then I think you could be in for a fair degree of mess around. 

If it were mine, I would be investing in an hour or so of the services of a trusted local diesel specialist. It would be worth enquiring for recommendations at your local taxi rank, since these chaps generally still use diesels and depend on a good economic turn around when things go wrong. Self diagnosis? I wouldn’t bother. There is a simple basic test for injectors, but you need specialist equipment. 

Perhaps you would let us know how you get on. 

Kind regards,

Gareth.