Hi all

As no-one replied to my last 'Pinking a bit' mail, I decided to be a bit more specific in the hopes that somebody out there can help!!! My Fabby VRS seems to misfire very slightly, causing the engine to judder at around 1800revs in any gear (at the appropriate speed for the gear). Above or below this rpm, the problem does not occur. Doesn't seem to matter if the engine is hot or cold!!

The dealer put it on the VAG-COM which showed up nothing and so they say that there is no problem. Car has only done 1500 (reasonably careful) miles and has behaved like this from new (1.5 months ago)

Any ideas gratefully received.

Suncat

"Pinking" usually occurs in a petrol engine due to overly advanced timing or a low grade of fuel. Knock sensors usually detect this & retard the ignition to suit.

A diesel engine cannot "pink" or misfire as there is no ignition spark or detonation.

I'd take it back to the dealer & get a mechanic to take a test drive with yourself & show him what's happening.

Thanks very much for your advise Jon

In my defense, I was aware that diesels can't 'pink' but it was the nearest analogy that I could think of, (being an ex petrolhead!). I'm completely new to diesels, so thanks for the explanation of sparkless detonation.

I'll try the 'mechanic's test drive route' that you've suggested. The dealer that I took out for a drive yesterday maintains that there was nothing wrong with the car even after he drove it whilst trying to replicate the fault on my instuction. I suggested that it may be slight turbo lag but he disagreed.

Suncat