I have an 80 280zx that has been sitting in a barn for the last 9 years. When I pulled it out I drained the oil and replace the filter and fuel filter, put in a new battery and 5 gallons of new fuel. (the person I bought it from said there was very little fuel in it when parked) When I turned the key and tried to start it the fuel pump failed to run. I replaced the fuel pump and the car started fairly quick. Since then I have replaced all the usual plugs, cap, rotor, wires, air filter ect. Currently the car starts and idles ok, however when you try to accelerate it backfires thru the air cleaner, it lacks power and accelerates very slow constantly backfiring in the air cleaner till you get to about 30 miles an hour. then it seems run ok but still lacks power. I have chased down several vacuum leaks and replaced and cleaned lots of connectors, put on a reconditioned AFM. Any comments ok suggestions will be appreciated