you would be surprised,i had a knackered cam on mine most off the lobes were pretty worn and on two cylinders the exhaust valve barely moved.ticked over smooth as silk,drove like a knackered,unchipped diesel!!! anyways if the cam is fine,and it really does only run on one bank then i would be looking in the ecu,s direction as mafs,coil packs,cam sensors etc would affect both banks equally.shame he,s not closer i would have had a shufti.ps it isnt the lpg either as that just mimics the petrol side and as i understand it ,it wont run on petrol either.