Hi, I was just wondering how you were progressing with your misfire? I too have a Countryman Cooper S All4 and from new (April 2011), I experienced an intermittent misfire on the engine, usually when going up hill (the dealer refers to this as under load). I drove the car for 6 months before taking it to the dealers, (re-occurring non starts in cold weather forced me to address the issue). Thirteen months on and two dealerships later I am no nearer resolving the misfire (I’m truly gutted). Here is the list of repairs and there may be more but I can’t remember:
• Multiple nox sensors
• Multiple thermostats
• Two lots of fuel additive
Multiple software updates
• Air intake pipe – (the car had suddenly started to make a noise similar to what you describe as tinny front exhaust rattle, they found a hole in this pipe which could cause the misfire – it resolved the noise but not the misfire)
The latest visit (of 5 weeks) has resulted in:
• Cylinder head been sent away to remove carbon deposits
• Engine timing being replaced and still the car was registering the same two fault codes with the dealer
Next steps are:
• Replace injectors again
• Carry out fuel tests
Although the first dealer eventually put the fault down to driver induced error (as if), I have to admit that the second dealership have pulled out all the stops when it comes to customer service i.e collect and drop off courtesy car, same day as fault re-reported. I am assured that mini technical have this raised to the highest level to get this resolve, but I can’t help thinking they haven’t got a clue what is wrong with it!
I hope you have more luck than me!