Really need some ideas on this ! Random dying issue

[Chevk587]

There should be a single red wire dangling from the fuel pump relay connector. If you put 12v to that, it sends 12v to the pump. If it does it again, and the pump wont run, put 12v to that wire...that will tell you if the problem is the relay or the wiring "downstream" to the pump.

Also, either your oil pressure switch isnt working properly either, it shouldnt die with a running engine regardless of the relay, or you have a wiring issue "after" both the relay and switch.

My issue is after the relay at the connector to the tail harness . Can’t get it to die Now but no broke wire or connector issues at this point .

 

[nvrenuf]

About 6-8 months ago I had to put a new fuel pump (in tank) in my Blazer and I had trouble with the connector. This was a Bosch brand pump, the supplied pigtail plugged right in to the factory harness but the terminals were loose, both in the plug and the male / female fit. This pump would randomly quit and/or run. I had to splice the wires to fix it.

 

[Chevk587]

About 6-8 months ago I had to put a new fuel pump (in tank) in my Blazer and I had trouble with the connector. This was a Bosch brand pump, the supplied pigtail plugged right in to the factory harness but the terminals were loose, both in the plug and the male / female fit. This pump would randomly quit and/or run. I had to splice the wires to fix it.

I’ll post a picture of the connector and wire tomorrow.

 

[dyeager535]

Oil pressure switch is hooked up and checked and bypassed once. No change.

If it wont run with the switch bypassed, and/or the relay pigtail with 12v to it, the problem is wiring in the circuit after those two. Tank ground, bad wire, bad connection, etc.

Both of those bypasses are a direct path to the fuel pump, no different than running a wire directly from the battery to the fuel pump, except you are using the stock wiring and all connectors in the circuit.

 

[Chevk587]

Ok I’m pretty sure my problem is solved had a bad wire /connection at the harness under the driver side firewall ran the trail with no issue !