Any help would be great. Driving my truck today and everything was fine, no stutters, or loss of power. Went to start it back up and it turned over and died. Now it will turn over but never start. Almost like there is no fuel. First thing I was going to try was to replace PCM and fuel pump relays. Checked inertia switch and no issues there. Any other thoughts?

 

Check to see if you can hear the fuel pump turn on when you turn the key to "ON" position.

 

I don't hear anything when I turn the key to the on position. Only a click from under the hood.

 

Click from under the hood with key in RUN(on) position is the EEC relay, that is good.

There should be another click right after(almost at the same time), that would be the fuel pump relay closing to run fuel pump for 2 seconds.

If you don't hear the fuel pump then either it is not being turned on or it has no power or fuel pump has failed.

What year and engine do you have?

In the fuse box in the engine compartment there is a Fuel pump fuse, fuel pump relay might also be there, depends on the year.

 

It is a 99 Ranger. Yes there is only the one click. I wait to hear the fuel pump run for a few seconds but there is nothing. I've had bad fuel pumps before and normally there is some symptoms of it going bad, well there were always symptoms when mine went out.

It is just odd to me that the truck was running like it does everyday and then won't start. Both FP relay and fuse is in the engine compartment.

Is there anything else you would check beside relays and fuses?

 

You can check for power at the fuel pump relay, or inertia switch.
Inertia switch is under glove box or in kick panel on passenger side.
It has 2 wire connections, 12v IN and 12v OUT, this is the fuel pump power sent by the fuel pump relay, so only has power IN/OUT when computer turns on the pump(relay).
It has a reset button on the top.
Inertia switch is there to shut off fuel pump power in case of the collision, this can be tripped by a large jolt hence the reset button, but should be replaced sooner than later if they are tripped, because they will trip again.

You could test for voltage at inertia switch when key is first turned on, should have 12v for 2 seconds, if it does then pump is bad again, or wiring at the pump.

If it doesn't have power when key is turned on then issue is at the relay end, it is not closing or doesn't have power to pass to inertia switch.

Battery-----fuse-----key switch-----EEC relay------fuel pump relay-----ground(computer)

Battery---fuse-----fuel pump relay(pass thru)-------inertia switch----------fuel pump---ground

 

So if there is voltage coming in and going out at the inertia switch then the likely problem is a bad fuel pump? Does it hurt anything to intentionally trip the inertia switch? I wasn't sure if the button was supposed to be up or down, and it was down so I popped it up and then down again.

 

Also, I thought I would add that my Check Engine light does not come on when the key is in the on position.

 

Update: Went to work on my truck and thought I would try to see if it stats since it's been sitting for two days. Truck started right up. Truck idled for 3 to 4 minutes and then died. Went to start it up again, and it will not start.

 

Some one has removed the bulb, usually to sell it.

Could be computer is bad, or wiring harness is lose, at the computer.

"Popping" the inertia switch will make it easier to pop next time, so yes it does hurt it.
Did you test if it had voltage for 2 seconds when key is turned on?
That would be a better test.

Fact that it started could mean fuel pump is working and fuel pump relay is intermittent, so fuel pump is not being turned on, but could also mean relay is fine and computer is not turning on the relay, so bad computer.
Test the 2 second voltage at inertia switch after key is on, if you have voltage but do not hear the pump then change the pump

 

Thanks, RonD for your reply.

My CEL has came on before, so it could be a bad bulb I suppose.

What could cause the truck to just die? It was idling fine, went to clear off the snow on the truck and it just died. It was not idling rough, or sputtering. I don't remember hearing the fuel pump run when it did start up. I will try and start it again tomorrow and check to see if I can hear the fuel pump run before I crank it over.

I believe I read somewhere that usually this issue is related to a bad PCM or relay. Also I have seen posts regarding a bad DPFE sensor.

 

Bad EGR system(DPFE) can stall engine at low RPM, EGR valve opening at idle will cause stumbling then a stall, but couldn't cause dieing while driving, would lack power but not stall(die).
Bad PCM maybe but long shot if stalling is the only system.
Bad fuel pump relay is a better "guess", it is a known issue but not what I would call common with your symptoms.

Bad fuel pump, could be, but simple test for 12v would tell you that.

 

Something else that is odd. I remember Sunday when I was checking the relay I didn't hear or feel it click. I felt and heard only the PCM relay so I thought well maybe it is just quiet. Well, I pulled the relay and connected it to a 9V battery and sure enough the click was loud and I should be able to feel it as well. Thought maybe power wasn't getting to the relay. Turned key to ON and probed the power and I have 12V coming to the relay. Very strange at this time.

Relay is good.

Power is coming to relay

 

With key ON there should be TWO 12volt contacts in the Fuel Pump relay socket,
key OFF one 12volt contact.

There is a full time 12volts from Fuel Pump power Fuse, this is the power to run fuel pump when relay closes
There is a key ON 12volts from EEC relay.

So make sure you have TWO 12volt contacts

 

Let me make sure I understand this correctly. I have a five pin relay. When I have the relay out I have continuity between pins 3 and 4. I then apply power to pins 1 and 2 and the relay clicks and I now have continuity between pins 3 and 5.

With key off, I should have only have 12V to one of pins 1 and 2 in relay socket and with key on both one and two should have 12V to each?

 

Only 4 of the pins are used.

From your description pin 4 would be unused.

1 and 2 would be the relay part(the coil), there should be high resistance between them but continuity as this is just 1 wire wound around a steel cylinder, which becomes a magnet when power is applied, this "magnet" pulls the contact arm down(the click) and connects pins 3 and 5 together, sending power to inertia switch.

So with key off pin 1 or 2 should have no power.
But pin 3 should have power, it should always have power, if you pull the fuel pump fuse pin 3 will lose power.

With key on pin 1 or 2 should now have 12v, this power comes from EEC(PCM) relay.

Any relays work the same:
pin---------wire wound around steel cylinder------------pin

This is "the coil", these two pins have no connection to any other pins.
Applying power to one pin and ground to the other pin creates an electric field which causes the steel cylinder to become a magnet.
The metal contact arm is held in one position by a spring, when magnet is on the arm is pulled towards the magnet, when magnet is turned off spring pushes it back to original position, this is the click you hear, the contact arm moving.

A 5 pin relay would be what is called a single pole double throw(SPDT) relay

The relay has 2 pins for the magnet on/off(all relays have these two pins)

Then 3 pins for the contacts
From your description pin 3 is the contact arm(so should have 12v all the time)
pin 4 is the contact when magnet is off(pin 4 should have no wire connected)
pin 5 is the contact when magnet is on(so this should go to inertia switch)

Google: image single pole double throw relay
You will see how these work

 

I have power coming to inertia switch. Fuel filter is old and rusty so I am going to change that out, easy right? Well I was able to get the outlet side off with no problem with one of those plastic fuel line disconnect tools. Inlet side I cannot for the life of me get that damn plastic DC tool in far enough to DC the fuel line. Anyone have any ideas, or are those plastic tools crap an dI should just get the metal ones?

 

They can be stubborn, put pliers around line and tap plastic removal tool.

 

For the inlet fuel line, if it is the kind with a white (or maybe yellow) plastic clip that goes thru the black plastic line end and holds the line onto the filter. Get a new one (or assorted sizes package) and I just broke the clip off (still took quite a tug to get the line off) and use a new retaining clip. That's how I did my 14 yr old factory original fuel filter (geeez).
If it's the metal spring retaining kind, I am not sure how to beat it.

 

Well, ran into a bit of trouble. One good thing is I did get the fuel filter off, but I busted the hose. It appears to be just around 6 to 7" of a rubber line that goes into a metal line and leads back to the gas tank. Is it possible to replace the rubber part and connect the quick disconnect fitting back to the line and connect the fuel filter. Or do I have ot replace that whole line on the inlet side?