94 Bonneville cutting off and not getting fuel pressure

[Blackflags]

A few months ago my car started cutting off when I drove it. My Dad and I realized it was losing pressure. I first replaced the fuel filter, then replaced the fuel pump with no luck. I checked the relay and it seems to be fine. I don't seem to have a MAP sensor on my car, which was something I was going to check. It will run for about 10-15 minutes before cutting off. No hiccups. I check the valve for fuel pressure after it cuts off, and it spits nothing out. It has to sit for a little bit until I can start it up again. When it runs, it runs like a champ. I've read online it COULD be the fuel pressure regulator. I disconnected the vacuum hose for this and ran it. Same thing. How would I even going about checking it properly?

Does anyone know what this could be? I will take it to a mechanic if I cannot figure out the problem myself. My uncle is here for a couple more days and is pretty good at working on cars. I'm not too bad myself. Any help would be GREAT. Like I said, it has a brand new fuel filter AND fuel pump!

[J Wikoff]

Any codes?

Sudden shut off, a lot of times can be the crank position sensor.

[CavemanDan]

Im no pro by any means. I do have 2 cents though. There is a green plug behind the battery thats not plugged into anything. This is for your fuel pump. Put 12v(+) right into that wire and your fuel pump will run. See if you can get that pump to run again right after the car quits. I have a feeling that your fuel pump hot or ground wire is getting shorted on the chassis. Also, GROUND BUSSES under the carpet on driver amd passenger side. Clean them.

[Blackflags]

Im no pro by any means. I do have 2 cents though. There is a green plug behind the battery thats not plugged into anything. This is for your fuel pump. Put 12v(+) right into that wire and your fuel pump will run. See if you can get that pump to run again right after the car quits. I have a feeling that your fuel pump hot or ground wire is getting shorted on the chassis. Also, GROUND BUSSES under the carpet on driver amd passenger side. Clean them.

I’m aware of the plug but never knew what it was for. I will check this. I was thinking it could be a bad ground. Thank you so much for the suggestion.

For the chassis, do you mean underneath? I’ve done a decent amount on cars but I don’t know everything.

[Blackflags]

Any codes?

Sudden shut off, a lot of times can be the crank position sensor.

It’s ODB 1.5, so getting the correct scanner and attachments will be costly. I’ve looked into it. A lot of people were saying with my year, it may not even spit out a code that helps. It might only point me in a certain direction. Would this have anything to do with fuel though? It’s like the pump isn’t coming back on.

[Blackflags]

Im no pro by any means. I do have 2 cents though. There is a green plug behind the battery thats not plugged into anything. This is for your fuel pump. Put 12v(+) right into that wire and your fuel pump will run. See if you can get that pump to run again right after the car quits. I have a feeling that your fuel pump hot or ground wire is getting shorted on the chassis. Also, GROUND BUSSES under the carpet on driver amd passenger side. Clean them.

Also, how would I check for a short? I’m sure I can Google it but I like talking to people. I have a multimeter.

[95naSTA]

Something else to look at:
http://www.automotiveforums.com/t254347 ... ville.html

Your fuel pump relay is position H in the relay center loacted below and to the right of the glove box. Here's the layout of the relay center:

A-----K
B-----J
C-----H
D-----G
E----- F
fuses 1-4
fuses 5-8

There is no position "I" for some reason. If your car is stalling upon start up then you could have a problem with the relay. However, if it has been running for a little bit the oil pressure switch actually runs the pump. The following is a description of the fuel pump operation:

Description and Operation
When the ignition key is first turned to the "ON" position, the ECM will energize the fuel pump relay for two seconds. This increases fuel pressure for cranking. If the engine is not running within two seconds, the ECM will shut off the relay and wait for a "START" signal. As soon as the engine is cranked, the ECM will energize the relay and power the fuel pump. Once the engine is started, the oil pressure switch provides power to the fuel pump. The pump will then continue operating as long as the ignition is "ON" and there is engine oil pressure. If oil pressure is low (enough to possibly cause engine damage) the oil pressure switch interrupts power to the fuel pump.

NOTE: The fuel pump relay can be bypassed at the oil pressure switch to operate the fuel pump. Also, a faulty oil pressure switch can cause the pump to run continuously whenever the ignition is "ON".

Your problem might be something other than the relay.

[Blackflags]

Im no pro by any means. I do have 2 cents though. There is a green plug behind the battery thats not plugged into anything. This is for your fuel pump. Put 12v(+) right into that wire and your fuel pump will run. See if you can get that pump to run again right after the car quits. I have a feeling that your fuel pump hot or ground wire is getting shorted on the chassis. Also, GROUND BUSSES under the carpet on driver amd passenger side. Clean them.

Update for you. We weren't getting anything from that clip. We jumped it there and started her right back up after the air came out of the line. She has been running ever since. We are talking close to an hour and I even drove her to the auto parts store. Still running. I'm going to hook in a toggle switch to it. This will be a $20 fix until I can get her into the mechanic. You have been the most helpful. Thank you so much for the information. I might even be able to run the wiring myself, but I would rather have a professional look at it!