tonupdave

PO codes are generic emissions codes from the EOBD system, in other words they are the same for all manufacturers so not that specific. 300 is random cylinder misfire and 301 cyl 1 302 cyl 2 as you state. Typical "faults" could come from engine mechanical, wiring, fuel, ignition systems - very general! I will be scoping all my sensors tomorrow so I will post the results asap, it may give you some pointers. Do you have any recent emissions data (from MOT)? Even if prior to the fault.

On further investigation the rear section of the exhaust is blowing which accounts for the high lambda reading which would make it run weak. I will do an emission test after the service and repair and post the results if this is of any use. Wakhtar, what are you using for the diagnostic testing that tells you 1&2 misfiring? Is it at idle and cold only?

I have a similar problem, on start up there ius a distinct misfire, with head under the bonnet there is the sound of a clicking relay comming from the throttle body which is accompanied by a sychronised movement of the throttle cable pulley. The problem seems to disappear one the car is warn and it drives normally. Only just got the car last week so not had a chance to investigate to far but am going to fully service this week (a quick check of the air filter suggested this would be a wise move). I do not have any fault lights on the dash and it just past MOT last Monday: Fast idle CO 0.06% HC 99ppm lambda 1.10 Natural idle CO .05% I will post results here on further investigation