THe inertia switch is a means to cut off fuel and spark in event of an accident. So you dont blow up, or do damage to your engine.
I havent had a fuel pump give me problems like that, the relay yes, but not the pump its self. I was going to say check you ignition module but you already replaced it.
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64 1/2 "D" code Red Mustang Coupe. 289, C4, Mallory duel point. Ported & Polished 65 heads shaved .01 with 351 valves, 11:1 comp, 1.7:1 rockers, blue wolverine lumpy cam, modified 4100 Hipo 4 barrel. GT Apperance pkg. And to many others to list
2000 Perf Red Mustang GT. 5spd. BBK Underdrive pulleys, Flotech off-road H pipe. Hurst T-Handle, 40 series Flowmasters
64 1/2 red 6cyl coupe. Auto. project car.
