1985 Chevy Cheyenne Turns over but won't start

Welcome to the forum. How long since a tune-up? With engine cranking, you have no spark at the plugs? Key on engine off, I'd check primary voltage at the coil, positive and negative/tach terminal. Engine cranking, the negative side of coil should have a pulse. If no pulse, check the ignition module and pick-up coil.

If the coil is in the cap, you can use a testlite on the tach terminal, the lite should pulse, cranking.