NO CODES 95 gp

have 95 grand prix 3.1 with 123000 mi. major loss of power and chugs up hill. changed plugs, wires, n computer but put original chip back in., injector cleaner. Its not showing any codes and hasnt ben since before changing out the computer. what should i try next?

ohm check the injectors. They should be around 12.6 ohms.

even though the computer in this car has an eprom, they are a programmable type, and you cannot swap it from your old to new ECM. You must purchase a new "blank" e-prom that matches the new ECM, then have that flashed to the car's VIN specs. That is where your problem is.