manifod has a leak on right side with that a tapping noise noticed only when driving not when sitting idling 97 tahoe 5.7 vortec

The tapping sound could be the exhaust leak at the exhaust manifold. Get the manifold replaced to see if the tapping sound goes away. I think there is a really good chance that it will.

Ditto to what Bob said. Exhaust leaks are often associated with a ticking or tapping noise.

What u hear is exhaust . It will burn the hole -leak out bigger in a short time .Fix it.