Hi all, having a bit of trouble finding the cause of an intermittent misfire. Since i have owned the car it has had this problem (obviously didnt do this on the testdrive). The car works fine for maybe 2 days, then when the engine is cold, it sometimes starts up and misfires badly. Sometimes the misfire lasts for 20 seconds or so, and with a few engine revs it dissapears. Other times the revs will fall and the car will stall, and refuse to start for maybe 10 mins. Up to now i have carried out some routine servicing. I have changed the fuel filter, the plugs, tried new coil packs, new diverter valve, used a bottle of fuel treatment (Redex), and identified 3 split breathers which have been replaced. i have cleaned the throttle body and re adapted it using VAGCom. I also have access to VAGCom. I am now struggling to identify the cause of the misfire. Anybody know if the N75 valve or the N249 valve could be the culprit? Obviously I dont want to replace these valves if i do not need to. I have a feeling that the car has had a front end smash sometime in its life. The ECU is logging the following codes: 17608 - Boost Pressure Control Valve (N249): Mechanical Malfunction : P1200 16795 - Secondary Air Injection System (B2) - Incorrect Flow or Secondary Air Injection System: Incorrect Flow Detected : P0411 16684 - Random Misfire Detected - Any Cylinder or Random/Multiple Cylinder Misfire Detected : P0300 16688 - Cylinder #4 - Misfire Detected or Cylinder 4 Misfire Detected : P0304 17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!) : P1297 16685 - Cylinder #1 - Misfire Detected or Cylinder 1 Misfire Detected : P0301 16687 - Cylinder #3 - Misfire Detected or Cylinder 3 Misfire Detected : P0303 17956 - Boost Pressure Regulation Valve (N75): Open Circuit : P1548 16686 - Cylinder #2 - Misfire Detected or Cylinder 2 Misfire Detected : P0302 16705 - Engine Speed Sensor (G28): Implausible Signal : P0321 16497 - IAT Sensor - Temp Low - Circuit High - G42 Anybody got any ideas to the cause or suffered similar symptoms? Thanks