Hi thanks for that i shall read the other post tomorrow I’ve read a Bosch manual explaining the operation of the ecu and components. If there is a fault detected in the variable valve timing. It also shuts down variable valve lift sets this to max and uses throttle body to control air intake volume....

Thanks to everyone whos been helping I've done most of the tests suggested. Swapped injectors no change Did relative compression test when running ok and as soon as misfire happens all within 4% Did physical compression tests as above all cylinders just above 10 bar Haven't got a pressure transducer...

Thanks
If i leave it running ecu turns injector 4 off.
What i don’t understand is change in secondary voltage of spark cylinder 4

Hi i have a 2011 1.6i its the Peugeot/bmw engine with twin cams and variable valve lift Fault code p1340 cylinder 4 misfire and multiple cylinder misfire I've had great difficulty recreating fault drives fine driven hard or labouring. Misfire only occurs when engine has reached 90degrees and you lea...