If a 92 Geo Tracker still won't start after replacing the fuel filter spark plugs and distributor cap could the coil be bad?

Yeah, the coil could be bad. You could also have a busted timing belt. Did you crank the car with the distributor cap off and see if it turns? You could have something as simple as a blow fuse in the fuse box too. As mentioned before, more info is needed to give you a better answer. I had that happen to my 1992 Tracker. It was the "The Brain" went out. I looked every where for a replacement for months. To find the Chevrolet dealer had it up the road. If that it ,it'll cost you,but my car has been running great for years now, it's worth it. if that's it ,get ahold of the chevorlet south fl. by homestead area.You say "still won't start": What exactly is the situation? When did it last run? More information is needed in order to diagnose your problem. It could be any number of things.