Need help on my 92 explorer

[bigtn]

I have a 92 explorer that won't start at all. I get spark at my plugs, have installed pump, relays, inertia switch, filter, and have checked the fuses. I can not for the life of me figure this out. I can not even hear the pump come on when I turn the key. Any and all help is much appreciated.

 

[Anime]

Check the battery? Battery cables? What happens when you turn the key? Click? Nothing?

There's two starter relays, one on the fender and one on the starter.

 

[bigtn]

It will turn over and will not crank. Battery cables are good and the battery itself is brand new. Haven't messed with the starter due to the way it stalled out had happened to me before on other vehicles, like it was struggling to get gas. That's why I changed out what I did and still won't go. No pressure on the lines turn it over and it still won't build pressure in the fuel lines.

 

[Anime]

If it's starting but just won't run that's different. Possibly a clogged fuel system, either the fuel filter, or a bad fuel pressure regulator. Could also be a bad pump or just a bad relay. Might also replace the PCM relay under the hood too just to try it.

 

[MrShorty]

I would figure out how to verify if the fuel pump is running or not. They are usually audible, so, at this point, I would probably get out a wiring diagram and a voltmeter and see if the fuel pump is getting power.

 

[bigtn]

Got power to the pump, relays check out ok and eec test checks out ok. The inertia switch also checks out fine. Pump still not turning on, what control unit is by the inertia switch? Is the pcm the module that is under the hood in the firewall?

 

[MrShorty]

Got power to the pump,

If you've got power and ground to the pump, there isn't much more to it - something is wrong in the pump or in the pigtail off of the pump. I do recall the first time I tested mine, I erroneously interpreted the 6-8 volt "ghost" voltage on the fuel pump circuit (coming from the PCM) as proof that the pump had power, but that's really the only major mistake I can see making. Well, except maybe for checking the wires to the sending unit, since they are in the same connector. If you feel you need to double check, do it again, but if you've convinced yourself that there is power and ground to the pump and it won't run, it looks like it is time to drop the tank again to see what is going on.

 

[Castorized]

I've had the same issue on my 94. I ended up jury riggin a new power wire from the relay itself right to the pump (only after then finding out the power wire in tank had broken). I don't suggest it as a fix, but tis my way to verify good or bad wireing.

 

[bigtn]

I thank y'all for your knowledge and insight to my problem, I will drop the tank tomorrow after work and let y'all know what happens. Y'all have been very helpful and hopefully tomorrow figure out what is going on with the pump.

 

[Castorized]

Save time and hassle on that one. Cut a 10"x10" square right under the seat, the top of the sending unit will be right there. have fun either way ya go . WEEEEEE

 

[bigtn]

Fuel pump works now, still not wanting to start. Will still turn over and not crank. Fuel rail not showing any pressure at all. Get spark and everything seems to be working. I only see one place for the what looks like a stem. Filter lines both showed fuel off the filter. Do not know what is going on with it.

 

[MrShorty]

If the fuel pump is running, but no pressure is generated, the next step usually presented in the diagnostic tree is to determine if there is fuel being returned to the tank. A few methods can be used:

1) audible - sometimes by listening to the tank, you can hear the fuel running into the tank. This can be the least reliable.
2) Carefully clamp off one of the soft sections in the return line. If the pressure jumps up, that indicates flow through the return line. If the pressure stays low, there is no flow getting past the regulator.
3) Disconnect the return line somewhere (at the regulator might be the easiest), then run the pump "briefly" (need to be prepared for gasoline to come out of this line).

In all cases, if gasoline is getting past the regulator when the pressure is low, that indicates that the regulator is stuck open. If there is no flow past the regulator, then there is something upstream of the regulator/fuel rail that is preventing the system from generating any pressure.