I've overhauled a mitsubishi Diamante '92 DOHC V6 engine. I've timed the engine, when I try to start it, it cranks but it doesn't start. I've changed the crankshaft position sensor and retimed the engine again. I've also check is there's fuel going into the cylinders, also if the spark plugs start. But it still won't start. Do any of you have any suggestions to what I can do?