As many other posts here, my 05’ Ranger won’t start. I’ve done lots to it and still nothing...here’s the breakdown:
-Engine will start with starter fluid
-cranks but won’t turn over (CEL comes on when cranking)
-don’t hear fuel pump prime when the key is turned to on position, so I replaced the fuel pump assembly and fuel filter...still don’t hear pump prime when key is in the on position.
-checked fuses and relays and everything checks out fine.
-replaced spark plugs, they were quite dirty
- checked the inertia switch, it was not tripped.
-check for fuel at the fuel rail, depressed the schrader valve and I don’t get any fuel coming out.

I feel like it’s a problem at the fuse box but everything checks out.

 

Welcome to the forum

CEL should come on with key on
CEL should go OFF when cranking, so typo?

You know where inertia switch is, so get a volt meter
Ground the meter to body
Then put meter on either inertia switch wire, dark green one is best

Turn on the key and you should see 12volts for 2 seconds then 5 to 8volts after that
Repeat a few times, key off and then on

If you don't see the 12volts then check fuse 23 in engine fuse box, test it or swap it with another 20amp fuse, also replace or swap fuel pump relay in engine fuse box

If you have a helper put your finger on the top of fuel pump relay and have them turn the key on, you should feel it Click closed and then open after 2 seconds, that means computer is working and turning on fuel pump power

Then try test again

If you have 12volts for 2 seconds at inertia switch but do not hear the fuel pump, then wire from inertia switch to fuel pump, the pink wire, is disconnected or new pump is bad

Battery positive----Fuse 23------fuel pump relay---------------------inertia switch----------------------------------------------fuel pump----ground

You can pull out fuse 23 and test that one of it slots has 12volts from battery, no key on or off it should have 12v all the time

 

Thanks. I will give it a try,, don't think it is the fuel pump because I originally replaced just the pump and still didn't hear it prime. So thought it might be the fuel pump regulator, so I replaced the whole assembly. Either way, thanks for the advice. I will return with updates....also something else. The truck isn't throwing any engine codes, thought that was odd.

 

There is no fuel pressure sensor so there wouldn't be any codes to set if fuel pump was not coming on
And there is no "no start" code
The fact it starts when you manually added fuel to the engine means computer is working fine as are all sensors

It can set secondary fuel pump circuit codes, P0231 or P0233, if fuel pump fuse or relay or wires to inertia switch were bad, but not always

Once you have access to top of gas tank test the fuel pump wires, pink one(12v) and black one(fuel pump ground) should see the 12v across those two for 2 seconds with key on, then 5-8volts after that
The 5-8volts is from the computer monitor circuit that would set the P023X codes, just FYI

Yellow/white and black/white wires at the gas tank are for fuel level sender

 

thanks for all the help, I am pretty sure I figured out what it was. Every time I check the inertia switch I just made sure it was depressed. I didn’t stop to actually unbolt it and check the connection. I did that and saw that the connection had gotten fried. Parts are on order. Thanks again. I will be back if replacing it and the pigtail doesn’t work.

 

Good work