If there is a knocking or tapping noise in a 1995 Firebird with a slight ping that is not coming from the engine and it only happens when you press the gas could it be that the u-joints are worn out?

U Joints can certainly make noise after they've started wearing and are dried out. If you have concern about an unfamiliar noise, take the vehicle to a trusted mechanic or even the dealer. It's nearly impossible to tell you what the noise would be from a description like that.