my 92 pontiac sunbird is making a loud ticking sound can that be fixed or is the motor unrepairable

Stuck valve, stuck rocker, broken valve return spring. It might be fixable, depends on how it happened. If the engine over-revved just before the noise started, you might have bent the valve and jammed it. Even that's fixable, but the cost might not be worth it. Do a compression test on each cylinder. If the valve is stuck open, you'll get no compression in that hole. Pull the valve cover, and check each rocker at to see which one is loose - that's the one with the problem.