FP continously running
Thread Starter
Pro
Joined: Oct 2009
Posts: 679
Likes: 0
From: vero beach florida
FP continously running
Would the 3 wire oil pressure switch breaking cause the FP to run until the battery went dead?
Because that is what happened, I hit it trying to see what I needed to get the steam pipe off and then I started to hear a gurgling sound in the fuel rails. Thought I had hit one of the injectors and it was loosing fuel pressure, well cam out this morning and the battery was dead. Soon as I hooked up the jumpers, gurgling sound came back and I went back and could hear the FP running, disconnected oil switch and it stopped.
I did not think the FP could run without the key turned on?
Because that is what happened, I hit it trying to see what I needed to get the steam pipe off and then I started to hear a gurgling sound in the fuel rails. Thought I had hit one of the injectors and it was loosing fuel pressure, well cam out this morning and the battery was dead. Soon as I hooked up the jumpers, gurgling sound came back and I went back and could hear the FP running, disconnected oil switch and it stopped.
I did not think the FP could run without the key turned on?
Burning Brakes
Joined: Apr 2006
Posts: 1,218
Likes: 7
From: Burleson Texas
This has happened to me on another project I was working on. The oil pressure switch is a fail safe if the fuel pump relay fails. When the oil pressure is above 8psi, the oil pressure sender/switch connects the circuit, bypassing the fp relay. This is in-case the relay has failed, the car will start.
What happens when the oil pressure sender fails? Well two things could happen, it wont work at all, or will work all the time. In your case its working all the time, when its only supposed to work above 8psi.
How do you fix it? Replace the oil pressure sender/switch. (sometimes there are two, a sender and a switch, replace them both) And as a precautionary, replace the fuel pump relay too.
To dispel a common misconception, this will not disconnect the circuit if the oil pressure is below 8psi if the fuel pump relay is working properly.
hope this helps
What happens when the oil pressure sender fails? Well two things could happen, it wont work at all, or will work all the time. In your case its working all the time, when its only supposed to work above 8psi.
How do you fix it? Replace the oil pressure sender/switch. (sometimes there are two, a sender and a switch, replace them both) And as a precautionary, replace the fuel pump relay too.
To dispel a common misconception, this will not disconnect the circuit if the oil pressure is below 8psi if the fuel pump relay is working properly.
hope this helps
