Hi. My wife's 03 A4 1.8T has been having a rough couple months. Once or twice every hour of driving... the engine will run rough and major power loss. No, I don't think it's the coils. They've been replaced in the last year. But if I had to guess, I'd say it's running on 3 cylinders.

Can an injector work... then not work... off and on? Or is it typically something that dies and it's done?

We did have this issue last year and our mechanic replaced one of the injectors. The car behaved for the next 8 months.

Typically it acts up for 10 seconds... or maybe even a couple minutes. But it always seems to straighten itself out. My usual mechanic is having a hard time diagnosing it because it never does it when he drives it.

Trouble shooting suggestions? I do have a basic unlicensed vag-com... but it doesn't seem to tell specifically which cyl is misfiring. I do have a Ohm meter, but it's not digital and I fear not accurate enough?