drdave88

iTrader: (3)

Just to confirm, this oil pressure switch should work in place of the two current ones from my V6 swap, one for the fuel pump and one for the gauge. Its from an 89 Vette. I will just need a 3 wire connector (PT121) and good to go.

http://www.napaonline.com/Catalog/Ca...676_0167106426

Pocket

iTrader: (24)

The oil sender is a simple one wire deal direct to the gauge. The fuel pump back-up switch is redundant and I prefer to remove them. Its only benefit is if your relay fails mid run, then the switch carries you until the engine is shut down. Then you're stranded unless you can build enough oil pressure during cranking

58mark

iTrader: (3)

here's the one that goes next to the oil filter. I replaced mine recently and it's great having a gauge again

drdave88

iTrader: (3)

Then just running ignition voltage to it would eliminate it, correct?

Pocket

iTrader: (24)

Swap the fuel pump relay trigger to ign. The sender doesn't require any outside voltage

drdave88

iTrader: (3)

Wouldn't running it to 12v ignition keep it running all the time in run position, even with the engine off? I don't want the pump running constantly if the engine isn't running.

Pocket

iTrader: (24)

It would, but how often is the key to the IGN position and the engine off? EFI systems have it that way, but with a computer shut off after X seconds

drdave88

iTrader: (3)

It wouldn't be all the time, but if I run into any issues and need to do some diagnosis with wiring where I will need power, the fuel pump will be on.

Pocket

iTrader: (24)

Unplug the relay then

drdave88

iTrader: (3)

So looking at the wiring diagram for this, there is a green/white on the fuel pump relay that goes to the ECM, does that need to be in the harness anymore? I assume I take the tan/white from the oil pressure switch and run that to 12v ignition.

Pocket

iTrader: (24)

The grn/wht wire is what I was talking about running of 12v IGN

drdave88

iTrader: (3)

So then the two wires for the oil pressure switch don't have to be connected to anything? I think those two were orange and tan/white (which are also splice into the FP relay). Or are those two just connected together?

Pocket

iTrader: (24)

I cut them out completely. Splicing them together will cause the FP to run continuously, even with the IGN off

The OPSU FP circuit is redundant circuit meant to back up the relay should it fail mid run. Since modern relays are much better than olden days, the circuit is no longer needed. A much better approach would be a fail safe to cut fuel if oil pressure dropped below a certain threshold

Here is a 90-92 TPI FP diagram. Notice how the relay and OPSU are on the same leg
http://www.austinthirdgen.org/mkport...ta_sensors.jpg

This is how I do it with swap harnesses
http://i150.photobucket.com/albums/s...uelControl.gif

The 12v IGN comment was for the grn/wht wire from the relay. Carb or non computer controlled circuit (switch) require 12v on this to run