hi carl exhaust blocked doesn't effect the pump relay pulsing and you would still get an even spark
paul i did check the cam sensor signal at the ecu and that was good but im worried about the crank sensor as i could do with some time getting my library up together until my scope exp gets better
and simon the battery on the vehicle was almost flat so i was using MY heavy duty GOOD set of jump leads and there was little difference and the volts were giving a good reading just under 10v on crank as my secondary 12v supply is 220ah at 12v deep cycle