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Recently finished doing an ls3 swap on my 2002 c5 corvette, and today is supposed to be tuning day. The car started up yesterday even with a rough idle prior to the tune.
come back today to start it and the fuel pumps won’t prime. Swapped relays had no luck, so I bridged pins 87 and 30 and the fuel pump kicked on.
at all pins I have
87-12 volts constant
86-12 volts constant
30 -0
last is the ground
so far the only lead I have is pin 86 and with the research I have done it’s only supposed to have 12 volts for roughly 2 seconds.
with the relay bridged the car runs and has no issue starting. So currently I am stuck with what could be causing this issue
87 and 30 are the “load” sides of the relay…one should be “hot” at all times coming from fuse 13…to check the other side connect a test light to battery POSITIVE and touch that other terminal going down to the fuel pump…the test light should light signifying power down to the pump and through the pump windings to ground…also check G401 which is the fuel pump ground near the left rear wheel well…there are a few connectors “C” 140 and 402 as you can see in the wiring diagram…you can check for power coming from the relay at the fuel pump since yours is accessible at the bottom of the fuel tank.
Fuel pump issue two days after ls3 swapped
