A3 emissions control system

[Bubbra6789]

Any help please i have a 2006 a3 2.0t i have got a emissions control system light come on the car is juddering when idling and sounds like a old tractor anybody had experience with this fault before?

[cuprabob]

Sounds like a faulty coilpack(s). Very common on VAG petrol cars. Connect to VCDS to find out which cylinder is misfiring or disconnect each one in turn to find out which is faulty. A new one vosts about £30 from TPS or dealer. ECP do cheaper Beru ones but I would stick to the OEM Bosch.

Emissons light is on because the lambda probe has detected the fuel/air mixture has not been burnt.

Edited by cuprabob on Monday 21st July 00:40