1994 stopped running at 65 mph

[tk1251k]

Driving on interstate last night 65 mph in my 1994 explorer engine just shut off no warning. Got to the side of highway checked the inertia switch button it was fine switched fuel pump relay no help. I know the fuel pump is not coming on cannot hear it anyway. I left it overnight 50 miles from home in charlotte I-485. It was dark and could not see much but I tried many times to get it started. I wish I had known about the eec relay because I did switch the fuel relay with the eec but if it was bad that would have not helped anyway. I noticed all relays are numbered the same on top of my 1994. Can a relay break down or stop working with no warning whatsoever while drving or would the fuel pump quit working that sudden. I think I may have it towed today. Any advice appreciated. thanks

 

[walterd140]

Oh yes they can. Usually they get hot & die. My truck would run fine all the way to work. But let it sit & try to start & I had no fuel pump. Wait 30 minutes & she started like new.
1 thing to remember is they are interchangable. I used my heater blower slot as a troubleshoot aid. Switched the blower (I can feel that work) with the fuel pump relay & the heater blower was inop.

 

[tk1251k]

Thanks it was pretty dark and I thought I may have mixed a couple of the relays up by interchanging them but you are saying they are the same. I dont think I pulled the eec relay though as I stated if I did I just changed it with the fuel pump relay and not start and switched them back which if one or the other were bad I assume it still would not send a signal to the pump. I want to make make another attempt at it since I am looking at a 50 mile wrecker bill. Thanks for the info

 

[lounge lizard]

you may want to check the CPS while your out there.

crank positioning sensors go bad just like that too. and I believe they are a cheap part to have on hand

 

[tk1251k]

Would that cause the fuel pump to not work because I cannot hear it activate with switch on at all? Thanks

 

[lounge lizard]

I'm not sure.
it may if the motor will not fire the pump would have no reason to pump. the injectors won't fire fuel if the ecm is not getting the signal to fire the spark.

at least that is what I was told.

 

[94Sport5Sp]

Hi

Your could also have a bad connection or ground at the fuel pump. There is an electrical connector up in the frame rail just behind the fuel tank. It is supposed to be clipped and therefore should not come apart. Mine did and the results were as you describe.

A simple test is to disconnect the inertial switch and test for power with a volt meter or test light. If power is there than relays etc are fine. I found my problem by accident. I had put a power jumper to the pump side of the inertia switch and then crawled under the x to test the connector behind the pump. As soon as I touched the connector the pump worked. Fixed the connector and all was well.

Just another thought
PaMnd

 

[tk1251k]

Good thoughts. I am going to check that plug behind fuel tank. It was an abrupt stall I thought about timing chain but I had to have first thoughts fuel or fuel pump since there is no activation with switch on. I need to check cps also. I wish I could have done more yesterday it was cold alot of traffic no lights wife worried we were gonna be hit by traffic that kinda stuff. Got home started searching and getting alot more info than I had in my brain.Thanks anymore suggestions appreciated.

 

[tk1251k]

Got it towed today. Checked the relays moved around. Inertia switch fine. Thought I would just check the codes but for some reason code tester acting weird. Cannot get computer signal. When switch is on No red light or anything but with switch off red light stays solid. I have checked codes many times never had this before . Does this point to the pcm maybe not sure , thanks

 

[tk1251k]

I found this morning the 30 amp fuse blown. I replaced it and it fired right up. Now the problem must have been either the fuel pump relay shorted or eec relay shorted. Since I moved the relays around before replacing the 30 amp fuse not sure which is which. I did not have any large 30 amp fuses so i traded the blown fuse with the abs fuse so of course its not working but I will get one for it later today.I hope the problem shows up on something else so I can pin point the bad relay unless there is another way. This forum has been extremely helpful once again.

 

[tk1251k]

I know this is an old thread but my problem happened onece again only this time replacing the 30 amp fuse did not work. I did more researching here and took Brooklyn's advice and un hooked the three wire plug to the tranny and it fired right up. So I thought I would plug it back up and it fired up again. So hope the pug was it not sure. I remembered the first time this happened almost years ago i had had the tranny out for repairs not thinking at the time that would have caused the problem and still may not have but you try to narrow these things down. Any will keep informed how it goes as I think its most important to keep those of interest iformed mon the outcome of these things.