Heres how it works:
Ignition on - 12vdc thru rd/lt grn wire to EEC relay energizing relay coil.
Coil energizes closing EEC relay contacts sending 12vdc from yellow wire thru red wire to wiring junction sending voltage to fuel pump relay, and several sensors and part of computer.
The yellow wires to the EEC relay and the fuel pump relay come from the terminal on the starter fender relay thru fuse links. Each relay is on a separate link, so check voltage from all links.
The computer senses voltage, and temporarily grounds pin 22 of the computer thru tan/lt grn wire. This energizes the fuel pump relay coil closing relay contacts sending 12vdc to the inertia switch thru or/lt blu wire and also pin 94 of the computer.
After a couple of seconds, the computer releases pin 22 shutting off the fuel pump relay, then waits for ignition pulses from the TFI module.
When the starter is engaged and the TFI module starts sending ignition pulses, the computer then re-grounds pin 22 closing the fuel pump relay supplying gasoline for engine start.
To test the pump, ground the tan/lt grn wire going to pin 22. With the ignition switch turned on, the pump will run as long as the jumper is in place.
If the pump starts, relays are good as is all wiring and fuses. If the pump doesn't start, you can diagnose back and see where the problem lies.
shady
I have no spark, what could cause this. I have replaced the tfi and i still get nothing. if i can get spark and bypass the fuel pump relay i think it should run???
One thing at a time. You are jumping all over the place replacing parts.
Check the EEC relay circuit. EEC stands for electronic engine control. This relay operates the computer. If the computer is not working, you are not going to have any spark or fuel output.
Use a test light, or meter and check the voltage path outlined in my post above.
shady
