I've basically just removed the rocker cover manifolds and given th :smug:e engine a good degrease. I've changed the seal in the dizzy too. replaced the plugs, dizzy cap and arm. Put in a new lambda sensor (abf engine) went to start it and it made a very loud pop/bang from the exhaust. I've removed the dizzy and this only seems to go on one way so can't be 180 degrees out. I did do a compression test on the engine so could it be unburnt fuel? Maybe Carbon cleaner down the inlet manifold? Should I try starting it again or am I likely to cause more damage. Any suggestions would be great!!