Hello,

My 2014 A4 Allroad has developed an issue whereby it will 'occasionally' get very lumpy at a stop with the engine running. It happened a month ago for a week or so, was good for weeks and today, its back. It like its dropping a cylinder at tickover and misfires. Its fine again when we move off. Sometimes, it ticks over nicely ...

Car has covered 130k and has just had a service replacing all spark plugs, air filter and a sensor on the top of the engine at the rear bulkhead.

My mechanic says that no codes are registered.  He has swapped coils around and has experienced the misfire himself.

Any ideas please?

Perhaps carbon build up? Might pay to check / do a carbon clean. My 2.0T is also due for one now.

Thanks for yoyr reply ... My mechanic suggested that that could be our next option ... strange thing is that it runs great some days?