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Where's the Chevy P30 fuel pump relay?

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Anyone know where to go about finding the fuel pump relay on an 89 P30 chassis with a 454?

We are vapor locking like crazy again, and I just put in ANOTHER electric fuel pump.  I'm going to pull the fuel line off and have Patti start the rig to see if fuel flows out, but if it does or doesn't, I'm starting to suspect either a bad fuel pump relay, loose wiring, or even a bad oil pressure safety switch going to the fuel pump.

We are out in the middle of nowhere, although I have a couple of generic relays that might work if I can find the suspect one.  And I'm not above rewiring the pump to bypass the OP safety switch if necessary, or rewiring the pump altogether temporarily to a toggle on the dash if!



Arent they down on the left side of the engine...almost under the drivers feat? I thought I read that somewhere?

Hey Kev You will have to get the specific wireing diagram for that veh. Looking thru my stuff nothing seems the same ! Usually fuel pump relays are easily accessable & have an open female connector close by to hot wire pump . One thing if you rewire the pump be carefull there are two wires at the sending unit one power for pump the other fuel gauge rheostate Do not supply 12 V to fuel gauge it will be destroyed or cause explosion !  If your veh uses a relay  The common Chevrolet relay wires are Tan & White , Orange 1, Orange 2 , Black & White , Green & White . The oil press switch supplys the ground for the relay when there is oil pressure . Frank

Thanks Frank!  First I'll pull the fuel line and have Patti start the engine to see if we have fuel flow.  Once that is confirmed...or not...I'll start checking the engine block for the oil pressure switches and make sure the wires going to them are connected.  Then trace that wiring hopefully back to the relay.

Thanks again!


Kev, my fuel pump relay is under the hood almost center and attached to the bulkhead. On mine there are 3 relays mounted together, fuel pump, ac compressor, and heater motor. These are Bosch  cube type relays, mine are black, but I've seen some gray ones on other GM vehicles. The relay will have four wires in it I believe. I'll look in my book  to see the color code in a bit, and post

Well the book shows 3 places it could be. 1 where I already said, 2 under the doghouse on drivers side, 3 inside of the frame rail in the rear.

The relay should have 4 but could have 5 or 6 wires in it.  The orange wire is 12v power, black= ground, dk/grn/wht is switched power, gray goes to the pump. It may also have a prime relay connected to it with red wires.


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