Loud engine click after tune up/intake gasket

I recently had my 98 Grand Prix with about 101,000 mile on it in for some major repair at the dealer I had the upper and lower intake gaskets replaced for coolant issues (over heating/lose of coolant) also had the 100,000 mile tune up. When I got the car back I noticed what sounds like an exhaust leak. I took the car back to the dealer they are telling me its dirty fuel injectors making that sound. I put some cleaner in the tank, but still making click noise. Any ideas?

Welcome to AF!

Injectors will click when they fire although they should not be loud enough that you could hear them unless you had the hood up. If you can hear the noise while in the passenger compartment then something else is wrong. I doubt you have an intake manifold leak but you could have a bad exhaust gasket where the crossover pipe attaches to the manifold. Common problem and not expensive to repair.

I can hear the click while I'm driving mostly while giving gas. Could this been caused from the dealer doing the tune up? I've been searching the forums and see you have to move the engine foward in order to get the rear spark plugs replaced. The dealer also told me they could not detect an exhust leak. Thanks for the help!