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2009 MINI Cooper, N12 engine, hot idle misfire on cylinder 2
Hey folks; I need to phone a friend on this waveform.
This is a capture of a hot idle misfire. What type of misfire do I have?
Compression on cylinder is 200; leakdown is 9%.
Eccentric shaft position is 24% (Valvetronic); idle speed is controlled by the DME altering the valve lift. Disconnect the intake camshaft sensor, and eccentric shaft drives to 171% and misfire is gone. Car runs great (no misfire) until it reaches operating temperature and engine speed is back to idle. As soon as you accelerate (valve lift increases) and misfire is gone.
I've scoped the #2 cylinder and the valve seats are where they are supposed to be.
