Q7 4.2 TDI "Missfire"

[bridgland]

My Q7 has recently shown signs of an occasional missfire, which happens at around 1750 rpm, which is just over 70MPH in 6th. It does it very briefly under minimal load and isn't there consistently, but occasionally. If I accelerate it shown no signs of misfiring through the revs, and you can feel it only at the 1750 rpm point. I have also noticed it in sport mode and when in 5th, the speed is a little lower, but the revs are the same.

I have it booked in for a service soon, but wanted to know if anyone might have seen this before (not sure how many 4.2 TDI owners there are out there).

Chris

[Dr G]

I haven't come across those specific symptoms; ECU will log a misfire though which will hopefully give your garage some good info to go on.

How many miles since its last fuel/air filters?

[KarlMac]

Sounds similar to the symptoms I had when my 2.0. TFSI petrol had a failing injector. A VAGCOM scan will flag up a number of codes.

[bridgland]

Dr G said:

I haven't come across those specific symptoms; ECU will log a misfire though which will hopefully give your garage some good info to go on.

How many miles since its last fuel/air filters?

Always nice to have the Doctor visit .

Last major service was about 22 months and 16,000 miles ago. It has supposedly had a minor service and an oil change since then.

[bridgland]

Service and VAGCOM check seems to have sorted it. Driving very nicely now and Torque Factor 11 fully engaged!

[Dr G]

Good stuff