i recently bought a 95 grand marquis it has sat for 9 years

Sitting that long and you have bad fuel in the tank is a sure sign the fuel pump is seized. Drop the tank, clean it and replace the pump assembly along with the relay, flush the fuel lines before putting the fuel tank back in so that crud doesn’t foul the new fuel and pump, then the fuel filter. Better change out all the fluids too due to moisture build up and the coolant cause it most likely has lost all protective additives and may have already started corrosion in the cooling system. This is the old Ford OBD1 system unless it was built really late 95 then it may have the early generation OBD2. I hope you have good luck reviving this Mercury icon.

Tank & pump are the answer, but to gamble, suck out the gas, put in a little fresh and a bunch of fuel system cleaner. Long shot. Gotta dissolve that varnish, but you'd have to disconnect the fuel from the injectors to flush.