I apologize if there are other threads on this. The other day, my father-in-law was driving my '91 Explorer and it just died on him. I assumed that the fuel pump quit becuase it wouldn't come on when the switch was turned on. I had a brand new lying around so I dropped the tank and put it in but it still won't work. I checked the inertia switch and it wasn't tripped. There is no power coming to the new pump at all. When the switch is turned on, there is a noticeable "click" inside the engine bay. Would that be the fuel pump relay making that "click"? Any other ideas on things to check? Thanks for any reading and any help.

 

It sounds like you've measured for voltage at the fuel pump, have you started walking your way back to the battery? Is there power at the inertia switch? If yes, there's an issue between the inertia switch an the pump. If not, then go backward one more step and check for power to the relay, etc.

You are also aware that the power will only be present for about 1 second after turning the key to run, and you won't be able to immediately cycle the key to get power again, you'll need to wait several seconds, correct?

-Rod

 

I do realize that power only goes to the pump for a second once the switch is turned on. I haven't gotten to check if power is getting to the inertia switch yet. I only got to check to see if it was tripped. And it wasn't. Today I'm going to keep back tracing voltage. When the key is first turned on, there is a "click" sound in the engine bay. I didn't know if the relay would/could make a "click" sound if it was bad. I've never had one go bad on any of my vehicles.

 

If the contacts of the relay are worn/damaged, the relay can still make an audible click but not allow enough current through. Many relays in the relay box are standard and you likely can swap the fuel pump relay for another relay as a means of doing a quick shotgun relay check. Just pick a relay for a function that you can currently confirm works properly (power window, horn, fog lights, etc.).

-Rod

 

I tested the voltage at the relay and it's only getting about 2.2 volts. What could be causing that? Bad ground possible?

 

Was this reading for the switched side of the relay or the relay coil? If the coil, were you using the ground for the relay coil to make the measurement or a solid, known ground? If using a dedicated ground, then a bad ground would not explain the low reading. A corroded connection somewhere in the power to the relay though could explain the lower reading.

-Rod

 

Hey Rod,
I just wanted to say thanks for trying to help me out. Sorry it's been a few days since I replied, but I've been beating my head against the wall trying to figure this mess out. I thought after I checked all the fuses, relays, connections, and the inertia switch, what am I missing? I just happened to watch a video 15 minutes ago where a guy was tracking down a similar issue on a Chevy truck and the first fuse he pulled was the EEC fuse. I ran out and checked it and it was blown. I replaced it and it started right up. Now the fun of putting the tank back in place begins. But first, I'm going to cut an access hole in case the pump ever does goes out. At least, in all of this mess, my Explorer got a new fuel pump and sock to replace the nasty half clogged sock and time bomb factory pump. It far outlasted its age with 233,000 miles. But anyways, thank you for all of your help and suggestions!

 

I'm glad to hear you got it running. Hopefully the fuse blowing was just a fluke, but it if blows again, I guess you'll be in for more fun.

-Rod