How to turn fuel pump on

[RangerBoi99]

I'm doing a carbureted v8 swap and need to turn the fuel pump on whenever the key is on. where and how do I accomplish this, I have found and been messing with fuel pump relay in the PDB to no avail

 

[Curious Hound]

I believe the pcm grounds the fuel pump relay coil. The power to the relay coil comes from the eec relay and is inly energized with key on. So, intercepting the wire from the fuel pump relay coil to the pcm and tying it permanently to ground should work. But I would have to verify that with a newer diagram later when I get home.

 

[pjtoledo]

how much of the original electronics are you using?
this is a 2000 manual, should be similar to your 1999, you do have a 1999 right?
the same basic circuit for a 2.5, 3.0, and 4.0
pin 40 at the PCM only monitors pump power, it does not supply power.

 

[Curious Hound]

Same as the older circuits. Take that LB/O wire 926 that comes from the fuel pump relay. Disconne t it from the pcm and ground it. That should give you constant fuel pump with key on.

 

[ShhhhhDougsHere]

@RangerBoi99 Your in great hands with these 2 guys helping you.

 

[RangerBoi99]

thanks guys! mine was 3.0 v6 before the conversion but I assume those relays are likely the same?
@pjtoledo it is a 1999