Fuel Pump Stress

[Gaylan]

I've got a '97 Explorer, I think I have a fuel pump problem. Can someone give me the voltages and their specific locations along the way to the pump? When I check the voltage at the pump connection with the key on I temporaraly get about 7.0 volts, then it goes to 0.00 volts. The issue I had was that as I was driving the vehicle started to stutter and lose power. It would idle fine, but when I stepped on the accelarator it just bogged out to nothing then it died and won't restart. 15 years old and 308000 mi.

 

[gonenuke]

Have you checked the fuel pump relay in the under hood fuse box?

 

[Gaylan]

I've checked the available voltages at the relay sockets, but not sure how to actually check the relay

 

[gonenuke]

Try swaping with the horn relay and see if it works. Or another of the same type

 

[Gaylan]

Did that on the side of the road immeadetly after the incident with no change. But haven't tried it in the shop where I can test voltages before and after.

 

[gonenuke]

Have you tested for fuel pressure? Have you tested for power at the inertia switch?

 

[deweyville65]

First, check battery voltage. Fuel pump will have battery voltage for 1-2seconds when you turn the key on, then drop to around 6V until you start the engine. Then it runs on full battery voltage. Believe me, I fought mine (96 4.0 OHV) for two days trying to get a good diagnosis before I relpaced the fuel pump. By the way, if the pump is not running, and the voltages check out. Try hitting the bottom of the fuel tank. Worked for me a few times until the pump finally quit all together. Turned out to be foreign material on the armature.