Misfire symptoms - but not a misfire!
My girlfriend has an '02 plate Mini Cooper which for the past two months or so has developed what has all the hallmarks of a misfire: hesitant under load, no power under about 3000 rpm until it eventually seems to catch and then pulls strongly, engine 'flutters' occasionally when driving at a constant speed etc.
So based on that she had the spark plugs replaced, no change. She had the coil packs replaced, no change. Plugging it into diagnostics has revealed no fault codes, so at the moment we're all stumped - including the garage!
Is this a common problem? At the moment I'm fearing all sorts: faulty injector, compression problems or god knows what! Can anyone shed any light?
It seems to be an intermittent problem too, sometimes it's terrible but other times the car drives absolutely fine and trouble free! It also seems worse when going uphill: whether this indicates a fuel supply problem or is just a symptom of it being under load I don't know....
All help greatfully received!