1999 Ranger Fuel Pump Issues
 

Hey guys. My 1999 4.0L v6 Ranger (auto trans) is having some issues. Recently the fuel pump won't turn on as normal when I turn my key. I have to turn the ignition on and off 10-20 times before I hear the pump kick on and I can start it.

Any ideas?

I already checked the relay and fuel pump shut-off switch. Neither was the bad.

Having to cycle the ignition switch That many times to get the pump to run, typically would suggest that the pump is going out, BUT before condemning & replacing it, maybe try/test a couple of other things to narrow it down to the pump.

Seeng as how the power relays are often problems & yes I know you said you've tested it, but we don't know how it was tested, so back probe the in cabin inertia switch output lead to the fuel pump when it runs, & that'll check most of the wiring & power relay feed voltage, for under load for voltage drop at that point. If feed voltage is low, try swapping the fuel pump power relay for a like one not needed to run the engine, like the AC power relay, just in case its contact resistance is corrupt & dropping voltage under load to the pump. If still no joy, it may be a contact or wiring problem beween the fuel pump power relay & in cabin inertia switch.

If under load voltage is ok at the output side of the inertia switch, then look to a wiring problem between the output side of the inertia switch to the fuel pump electrical connector, or the fuel pump itself.
So, try wiggeling the fuel pump power connector with a coat hanger or other "feeler", to see if maybe the electrical conections atop the pump may be corrupt.

If still no joy, try thumping the pump with a stick, or back handing the bottom of the fuel tank, to see if a good thump will wake the fuel pump up. If so, its likely pump replacement time.

Its said by those that have had to replace the fuel pump, that its easier to unbolt & move the bed back to access the pump atop the fuel tank, than to empty & drop the tank.
So to move the bed back, you'd disconnect the tank fill hose, rear lights electrical connector, remove the tail gate to make things lighter, remove the bed bolts & slide the bed back to rest on the rear tires & saw horses, to have plenty of room to access & remove the fuel pump from atop the tank.

More thoughts for consideration, let us know how your trouble shoot goes.

Without a lift and proper jack, much easier to pull the bed . Even with a lift it is sometimes easier to pull the bed than drop the tank. My wife helped me move the bed on my 91 ranger .All said, pump replacement took less than an hour .

How do I check the voltage?
Sorry, I'm new to electronics in cars. I got the engine down, but all these wires have me confused.

Use your multimeter on the 20 vdc range. Back probe the in cabin inertia switch output lead that goes to the fuel pump, with the meters + lead probe, the meter - lead probe on a clean, unpainted, no rust, metal body connection point & post the voltage number measured. The two second KOEO voltage should be very close to the reading you'd get measuring across the battery posts.

You need a volt meter . Digital ! Ck voltage at shut off switch to start . You should have battery voltage with key on at start and a few seconds before start . If good there ck at fuel pump . Your voltage should be close to battery voltage .

Wow I'm a slow tiper !

First time I've ever managed to out type/post anyone!!!! Its usually the other way around for me, nice to finally win a posting contest!!! lol

Anyway hcraw4d, break out that multimeter & put that puppy to work, before throwing a fuel pump at the problem. You can get one from a place like Harbor Freight for less than $10, thats good enough to learn on & if you blow it up learning to use it, not many $$$$$ lost.
In case you find an electrical connection causing a serious voltage drop, the "Battery Tutorial" link atop this forums index page has instructions on how to use your multimeter to do electrical connection voltage drop testing, that sure can help in trouble shooting electrical problems & save us mucho $$$$ from not throwing parts at a problem & hoping for joy.

Thanks pawpaw! I'll get on it tomorrow morning, first thing!

OK, let us know how your trouble shoot goes.

[quote=pawpaw;12656194]First time I've ever managed to out type/post anyone!!!! Its usually the other way around for me, nice to finally win a posting contest!!! lol

I blame the eyesight and arthritis for my slow typing . Well that is what I will go with ! LOL !:-X0A6