If the engine runs and no trouble codes, the last number difference might not matter. You are right about the PCM possibly being damaged by jump starting, even if the connections were correct, it can cause such problems as well if the ignition key was left turhned on while connecting the jumper cables and power surge can be damaging.
The noise is definitely not from the PCM. It is engine internal and hopefully it is from the valve lifters which might go away after some running.
A more serious cause would be worn con rod bearings. If the noise increases in intensity/level with sudden/abrupt acceleration, that could mean bad news. If the noise is intermittent and is also present wile idling, that would be from the valve lifters.
The grey smoke is engine oil being burnt in cylinders or getting to the exhaust via the valve seals and f it is minimal, there is nothing to worry about.
The odd smell would depend on what smell. It could be the oil burning or a bad catalytic converter. Ensure the engine is not misfiring.
Tuesday, November 13th, 2012 AT 1:42 PM