Starting Issue

[arcticguy57]

I've got a 92 Explorer w/ 4.0, 5 speed. I love this rig and this is the first problem I've had with it in 40,000 miles. Today, while driving home, she just died. I got it off to the side of the road and tried to restart it. I could hear the fuel pump whirring when I powered the key. The engine would start and idle roughly for a couple of seconds then die again. Pumping the accelerator did no good. I checked my fuses, all good. Is it possible the pump is still making noise at power up but not working? How do I check the fuel pressure? I'm also wondering if it could be the fuel pump relay? Thanks in advance.

 

[Roadrunner777]

There is a port to the fuel rail on top of the engine, It points up and out to the passenger side, close to the air box. It has an internal valve like a tire stem. You can buy a fuel pressure gauge that will screw right on to it. I forget the exact pressure spec, but someone will have it handy. The fuel pump relay, if I understand, is only used for starting. The computer takes over after that. Could be a pressure regulator, but I don't think it would even start if that were bad, but maybe.

Edit: If it is like the 94, the PCM and the fuel pump relay are both capable of supplying power to the pump. This circuit may be hard to test because of access. I would do the pressure test and come back here with the results.

 

[FIND]

Check your fuel filter and fuel pressure regulator.

 

[arcticguy57]

I went out this morning and it turns over fine, however, it won't fire at all. I changed the fuel relay, no change. How do I depressurize the fuel system when the engine won't run. I'm off to the parts store to get a fuel pressure gauge and a new fuel filter.

 

[Roadrunner777]

The port has a tire stem type valve, if you poke something in, gas should spray out, or maybe it will drip in your case. I do not know of a friendly way to depressurize a fuel line. The fuel filter has funny clamps, I hope you or the parts guy catches that. It takes a special tool to do it in the way it is intended.

 

[arcticguy57]

Roadrunner, I pushed in on the shreader valve and nothing came out, so I guess the system is depressurized. I'm going to put my goggles on and have rags ready and remove my fuel filter. Does the lack of pressure in the shreader indicate it's probably the fuel pump?

 

[Roadrunner777]

Fuel filter, fuel regulator, fuel pump, in order of cost and pain to work on. I'll hope for fuel filter.

I just looked up Wasilla, I'd like to retire and be your neighbor, I love mountains.

 

[arcticguy57]

It was the fuel pump! I replaced the fuel filter then I replaced the pump and she fired right up. I cut a section out behind the rear seat, from one of the sticky's on here, and accessed the pump from above. That made it real easy. Figuring out how to disconnect the fuel lines was a PITA but once I figured it out, it was really easy. Oh Yeah, I now have a gas gauge! I haven't had one since I bought the truck. This is an awesome forum and thanks for all your help. Roadrunner, Alaska is beautiful and if you haven't visited it, you should.

 

[Roadrunner777]

Great News! Well, it had to be the PITA one, and the expensive one, but at least it's running happy.