My return setup has the fuel pumps come on as soon as the key is on and they just stay on but that's kinda ghetto. I'm wanting to get it work like OEM where key on means the pumps prime for a second or two and then go off. Crank the car and pumps are on, engine running pumps are on. If motor were to stall pumps go off after a second or two.
Anyone figure out how to make that happen? I was thinking of building an electronic circuit to do it. Use one of the outputs from the ECC that's only high when the engine is running to trigger it. If someone else has already done all this though no use in re-inventing the wheel. Thoughts, ideas?
Thanks
Malcolm
EDIT - I figured out the solution towards the end of page 2. Here it is for those searching and finding this thread.
SOLUTION:
OK when I first wired up my pumps return style my thought process was to remove the FPDM from the equation as it's no longer needed. Instead I took the DG/YE wire (pin 9) as everyone suggested and used it to power my relay. The downside of course is the pumps run continuously when the key is on regardless of engine running.
The signal wire from the ECC is the WH/R at the FPDM side (pin 1). It provides the correct times for the pumps to be on such as prime and then off when motor is off. It alone however is to weak to drive a relay.
So the solution is as simple as using the FPDM output that would normally drive a fuel pump to drive your relay. Use pin 10 & pin 3 to wire your relay. This way the ECC still tells the FPDM when the pumps should be turned on and the FPDM in turn activates your relay.
Pin 10 = BN/PK (normally fuel pump positive)
Pin 3 = RD/BK (normally fuel pump negative)
Note: you must use pin 3 to ground the relay coil (trigger) and not chassis ground or it does not work.
There you go guys!!
Malcolm
EDIT: pinout
Anyone figure out how to make that happen? I was thinking of building an electronic circuit to do it. Use one of the outputs from the ECC that's only high when the engine is running to trigger it. If someone else has already done all this though no use in re-inventing the wheel. Thoughts, ideas?
Thanks
Malcolm
EDIT - I figured out the solution towards the end of page 2. Here it is for those searching and finding this thread.
SOLUTION:
OK when I first wired up my pumps return style my thought process was to remove the FPDM from the equation as it's no longer needed. Instead I took the DG/YE wire (pin 9) as everyone suggested and used it to power my relay. The downside of course is the pumps run continuously when the key is on regardless of engine running.
The signal wire from the ECC is the WH/R at the FPDM side (pin 1). It provides the correct times for the pumps to be on such as prime and then off when motor is off. It alone however is to weak to drive a relay.
So the solution is as simple as using the FPDM output that would normally drive a fuel pump to drive your relay. Use pin 10 & pin 3 to wire your relay. This way the ECC still tells the FPDM when the pumps should be turned on and the FPDM in turn activates your relay.
Pin 10 = BN/PK (normally fuel pump positive)
Pin 3 = RD/BK (normally fuel pump negative)
Note: you must use pin 3 to ground the relay coil (trigger) and not chassis ground or it does not work.
There you go guys!!
Malcolm
EDIT: pinout
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