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My 94 explorer wont start...the lights are working so idk if it would be the battery ...it turns over and sounds like it wants to start up but it wont..like its not getting enough spark or something I have no idea. It was working fine a few hours ago..this is my only vehicle I need any kind of advice.  I just put gas in it a few hours ago..wasn't much but its in there. I seen online something about a relay fuel switch I have no idea what that is or if that could be it...I just need some help!! Please!!  

when you turn the key on..   can you hear the fuel pump start running for about 2 seconds..   just a quiet hum from the fuel tank????

this sounds like the fuel pump is failing...

this is going to take 2 people...    one to crank and start the engine.. the other to lay under the side of the truck and pound HARD on the bottom of the fuel tank WHILE the engine is being cranked...

this little trick has gotten so many cars and trucks started.. i wish it was more wide spread..

fuel pumps have brushes to transfer power to the armature..  these wear out..   pounding will most of the time.. while the engine is being cranked.. get the brushes back into contact to spin the pump up again..

this is the fuel pump assembly.. it hangs from the top of the tank...  the white strainer is right at the bottom of the tank




this is the fuel pump by its self as it usually gets replaced..


you will also need one of these..




the inertia switch is usually located in the panel to the left of the drivers feet..  there is a round opening in that panel.. where a pull handle in.. usually a on a flat area right under the pull handle.. you can stick a finger into that opening and depress either the round button or the long bar..  if you feel it snap as you push it.. that means it was tripped.. its a steel ball held up by magnets.. bridging the contacts.. this is like a tilt switch on a pin ball game.. if you hit it hard enough. the ball falls away shutting off power to the fuel pumps..


this is one style of the inertia switch..  i think you have one with a white bar where the red button would be..




one last thing.. until you reply..  

this is the ignition switch..  i have had the plastic sections of these fall off..  test other things like the power windows.. do they still work..   the little metal fingers at each end are the only thing holding the plastic bottom in.. and there are springs inside trying to push it apart..  the springs are the holding the sliding contacts tight against the face..





if you have to buy the parts your self for the fuel pump.. check the pricing on the entire fuel pump assembly.. i noticed its only about 30 bucks more than just the pump....  

i should mention.. that blocked fuel filters have damaged a LOT of electric fuel pumps..

this is the fuel filter..



see the 2 plastic horse shoe shaped clips.. those need to be replaced at the same time..

try not to break the plastic ends of the fuel line assembly..

you can unplug the fuel line from the fuel filter.. turn the key on and the pump should pump for 2 seconds..

when the filters are plugged..

the filter when it gets restricted makes the fuel pump work harder.. drawing more amps.. this burns the brushes out and wears the commutator down.. until the fuel pump fails when the brushes don't make contact any more.. or the motor stops without enough contact from the brushes..  

I had a friend who works on cars sometimes try spraying engine starting spray and it still wouldn't start..they said if it was the fuel pump t should have started. They also tried knocking on it and nothing different.  They said its probably not getting a spark somewhere...I have no idea what that means...is that the spark plugs?  

there are a bunch of things that it could be .. .

there is a bunch of stuff to check....

i have a project right at this second..

you are going to need to check for power to one of the wires to the coil.. plug in terminal...

there is a main relay and a fuel pump relay to check..

what happened with the ignition switch...  i have had to change a LOT of them... did you pull the lower column cover and take a look that it is intact .. and not falling off..  

you might want to if you intend on fixing this your self.. take a short subscription to eautorepair.net  or alldatadiy.com   both are factory service manual info providers..    and fords are complicated for diagnosis..

do you have a digital volt meter..   a test light.. a timing light to check the spark..  an OBD1 scan tool with the EEC4 connector so you can run a KOEO test...  for stored trouble codes????  Key On.. Engine off..

more to come when i get done...  

you will want to print images 1 through 7 on this page...

http://www.autozone.com:80/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0996b43f802c5495


click the enlarge button .. there will be a print image button in the upper right corner..  

you will also need to print image 29 from this section..


its the engine control wiring diagram... for the 94 explorer...

http://www.autozone.com:80/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0996b43f802c54bb