I have a 94 cobra, and after it runs for awhile, and I shut the car off, when I turn the key back over to on, the fuel pump just keeps turning on and off on and off, would this an inertia switch, fuel pump relay, or any ideas? Thanks in advance.
Check for codes.
Because of the cyclic nature of the priming, it is likely NOT the inertia switch, FP relay (itself), etc. It could be a puter issue (sending a ground pulse to the FP relay repeatedly), a bad ignition switch connection (the puter keeps thinking you're turning the key on), etc. You should be spitting a primary or secondary fuel circuit code with this issue. That could help narrow it down.
The underlying theory: when you turn the key on, the pump primes for 2-5 seconds. It remains off until the PIP circuit is active, at which time the pump runs non-stop.
Could this be a ignition module problem also JT?