2002 Explorer XLt 4L 4x2 cranks but won't start

[Bizzly]

Ok, here we go. I like to think I know this truck well after 17 years but she has stumped me. 4 months age I drove her home as I have for years now. Came out the next morning and cranked her over but she would not start. Strong crank but no start.

Considering I have never changed a fuel pump, timing chains or the fuel filter I knew I had some research in front of me. I was able to get it to fire and run on some starter fluid for a few seconds. so I researched the symptoms of a bad fuel pump and found out I could not hear the pump prime the injectors and there was no fuel pressure at the fuel rail schrader valve. I checked fuses and relays and found they all looked and acted good.

I decided the fuel pump was most likely the issue so I did the short cut process and cut a panel out of the passenger side floor board. It took less than an hour with the use of an air chisel to cut the access door. I had ordered a new pump and installed it. The whole job took two hours and I did not even jack up the truck.

All of that was for not though because we are still in the same position and she still will not fire up unless i feed her some starter fluid. Then she only runs for a few seconds (runs smoothly though). Still does not create any fuel pressure and the pump does not run. The fuel gauge does show the correct fuel level and i have tested out the inertia switch (it tested good on the ohm meter). This is a first year Gen III early build.

I am close to having it go to the shop but I am more than willing to try a few ideas if anyone has some and maybe has dealt with something like this them selves. All suggestions welcome.

 

[974X4BLACKSPORT]

Did you check or change the fuel filter when you changed the fuel pump in the tank out? A clogged or very restrictive fuel filter can cause symptoms you are describing.

 

[Bizzly]

Next on the list. However it dose not even prime the injectors when I move the key into the run position just prior to starting. Would a clogged fuel filter prevent the 1 to 2 sec priming from occurring? Also it never acted like it was starving for fuel prior to the start of the issue.

Thanks for you response.

 

[TechGuru]

See if this helps you:

Relay power is provided by fuse 39 (15A).
Fuel pump power is provided by fuse 26 (15A)

 

[Roadblock1945]

Going through this right now. Have someone crank the SUV as you smack the bottom of the gas tank where the swirled coil shape is, that's where the pump sits.

Use the palm of your hand or a rubber mallet. I get the EXACT same thing you are and its a stuck fuel pump for me.

Mine finally DID die all the way about a week ago. Just bought a DeWalt angle grinder, going in through the floor!

 

[Bizzly]

Air chisel from China Freight "Harbor" is the the fastest tool to get though the floor pan, pneumatic cheese knife. Blew right though without a single spark.I switch out the pump with no change. getting ready to take it to the Garage......

 

[mbed]

Air chisel from China Freight "Harbor" is the the fastest tool to get though the floor pan, pneumatic cheese knife. Blew right though without a single spark.I switch out the pump with no change. getting ready to take it to the Garage......

A better tool is the sheet metal shears from harbor freight:
14 gauge 4 Amp Heavy Duty Metal Shears
used it a few years back and posted a video...

 

[mbed]

Ok, here we go. I like to think I know this truck well after 17 years but she has stumped me. 4 months age I drove her home as I have for years now. Came out the next morning and cranked her over but she would not start. Strong crank but no start.

Considering I have never changed a fuel pump, timing chains or the fuel filter I knew I had some research in front of me. I was able to get it to fire and run on some starter fluid for a few seconds. so I researched the symptoms of a bad fuel pump and found out I could not hear the pump prime the injectors and there was no fuel pressure at the fuel rail schrader valve. I checked fuses and relays and found they all looked and acted good.

I decided the fuel pump was most likely the issue so I did the short cut process and cut a panel out of the passenger side floor board. It took less than an hour with the use of an air chisel to cut the access door. I had ordered a new pump and installed it. The whole job took two hours and I did not even jack up the truck.

All of that was for not though because we are still in the same position and she still will not fire up unless i feed her some starter fluid. Then she only runs for a few seconds (runs smoothly though). Still does not create any fuel pressure and the pump does not run. The fuel gauge does show the correct fuel level and i have tested out the inertia switch (it tested good on the ohm meter). This is a first year Gen III early build.

I am close to having it go to the shop but I am more than willing to try a few ideas if anyone has some and maybe has dealt with something like this them selves. All suggestions welcome.

I have an early build 02 with nearly identical diagnoses!

 

[kydirtscooter]

Inertia fuel cut off switch good? Try to reset and check for continuity. These sometimes act up, have had them go off after jumping trucks before. Also have heard of them randomly tripping. That cuts off all power to fuel pump

 

[Bizzly]

I ohm tested the inertia switch and it seems to be good. Is there a way to bypass it all together? Not familiar with the connector.

 

[kydirtscooter]

I wouldnt bypass inertia switch.

 

[kydirtscooter]

Starting at pcm, there is a 58 pin connector.
-what is key on power at pin 2, PK/BK?
-can you feel/hear fuel pump relay make contact?


At inertia switch
-pin 1 should have power
-pin 2 (middle) should have power ( otherwise it is tripped)

If you have power this far, then you are looking for a broken wire between tank and inertia switch. There are 2 connectors you can test for voltage, C2095 pin 37 of a large connector right under fresh air door has 74 pins PK/BK and C3047 which is covered b a shield, on the outboard side of frame pin A should have voltage PK/BK.

What is the resistance between pins 7 of fuel pump plug and ground?

Is resistance between pins 7 and 3 at fuel tank connector showing open or not?


The fuel pump is simply an electric motor it just wants power and ground so check power path all the way back. Just for fun, hook the old pump up to a battery. Does it run? If it does either chassis wiring or control is to blame.

 

[mbed]

I ohm tested the inertia switch and it seems to be good. Is there a way to bypass it all together? Not familiar with the connector.

Found my problem to be a minor crack in the clip that holds the wires to the inertia switch. It seems that the wires had sporadic contact and would sometimes prevent starting due to intermittent lack of continuity. Scavenged a new connector from a wreck...

 

[kydirtscooter]

Sometimes can be the strangest thing that causes issues. Connection terminals can be issues.