Hey guys cheers again got the car running again turn out I some how knock of the sender wire of the starter motor when work on the car not really shoreb how but any howhow's now I've got the engine running new problem has arised

I'm getting a tapping sound from the left side but only when in gear and under load but if the car is in park or neutral I can rev the crap out of the engine and not a single tapping noise go back in to drive and give it a little bit of peddle and the tapping starts again ???

Checked all spark plugs
Oil levels are spot on with good new oil and filter
Engine runs great as long as not in gear ???

My guess is exhaust manifold gasket.