I'm completely stumped on this and it feels like I've tried everything there is to try. I'm having trouble starting my 1992 Ford Ranger 4.0 V6 I've replaced the starter, starter selenoid, clutch position sensor, battery, fuel pump, fuel regulator, fuel filter, and all liquids besides brake and clutch fluid. I've tested to see if it was a mass air flow sensor or a TPS error but it just won't start. I'm not too sure what else to try or look for. I've got fuel going to the engine and I've got spark and combustion. Just not too sure what else could be stopping the truck from starting

 

Welcome to the forum

You are describing two different problems?
No Crank(starter motor doesn't come on and turn the engine)
No Start(engine turns but won't start/fire)

No crank
In 1992 there will be a starter relay on the inner fender, 2 large posts and 1 small post, the relay's metal base must have a good ground to metal inner fender, which also must have a good ground to battery Negative(people often call this relay a "starter solenoid")

One of the larger posts will have battery Positive wire, AND several other wires attached, this is the 12volt distribution point for the WHOLE vehicle
Other larger post will have ONE wire attached, goes to the starter motor
The Small post activates the Relay
Wire on the smaller post will be Red with blue stripe
If you jumper 12volts from battery positive to this small post Relay should "click" closed and starter motor should activate
If relay doesn't "click" closed then battery is dead or Relay is not grounded, OR relay is bad
If Relay "clicks" closed but starter doesn't come on then starter is bad or mis-wired, FYI, "new starter" means NEVER EVER tested starter, not "it works" starter

If jumper gets Relay to "click" and starter to activate, then relay and starter are GOOD
Next
Red/blue wire should have 12volts when key in the cab is turned to START
The dash lights should come on with key on, this means ignition switch has 12volts present, no dash lights means no 12v at ignition switch so no 12v on red/blue wire in START

No dash lights with key on means, in 1992, Fuse 10(60amp) in engine bay fuse box is blown, OR fuse box's RED wire on larger starter relay post is bad

If dash lights work but no 12volts on red/blue wire at starter relay then ignition switch or "clutch switch"(manual trans only) has bad connection
Clutch switch will have a red/blue wire(12v IN) next to a Pink wire(12v OUT) on its 6 pin connector
These 2 wires need to be connected together to send the 12v to starter relay, clutch switch does that when its compressed, i.e. clutch pedal down all the way
But you can unplug the clutch switch and jumper these 2 wire together for a test

Fuse 10---------(yellow wire)------------ignition switch-----(red/blue)-----clutch switch----(pink)---------//------(red/blue)------------starter relay

// = firewall connector

 

Sorry I thought I was describing a no start, the engine cranks but won't fire up

 

Yes you did but also had, "I've replaced the starter, starter selenoid, clutch position sensor.........", which are no crank issues


Do the 50/50 test, this is actually the ONLY WAY to test for spark on a Ford Waste Spark system
Remove the air tube on the upper intake, make sure it can't hit the fan
Open throttle and Spray fuel into the upper intake: gasoline, ether(quick start) even carb or brake cleaner
Try to start engine
If it starts, runs and dies then you have a fuel supply issue
If it doesn't fire/start then its a spark issue
50/50 instant results on where to look next

Other tests
Crank engine over a few times
Pull out any easy to get at spark plug
It's TIP should be WET with fuel, if its DRY then no injector pulses from computer or no fuel pressure from pump, or no timing pulse from EDIS-6 module(more later)
If Tip is WET, light it with a match or lighter, should burn fast and bright, if not then its not "fuel", its water or varnish

If Tip burns then a no start is now a spark issue, or compression, lack of compression with the 4.0l OHV would be a very rare occurrence, but if you have a compression gauge test 1 or 2 cylinders just to take that off the table, expected is 145+psi

1992 4.0l OHV used EDIS-6 spark system, separate from the computer that runs the fuel injectors
It has a Crank sensor, EDIS-6 module, and the coil pack
The system is fairly bullet-proof unless vehicle was ever in a front end collision, as the EDIS-6 module is on the Rad support
Crank sensor sends a timing pulse to EDIS-6 module once engine/crank is turning
EDIS-6 times spark to coil pack using that signal, it ALSO passes that signal on to the Computer so it can time the injectors

1992 should have a CEL(check engine light)
CEL should come on with Key On, that means computer has powered up OK, no CEL = no computer and no start
CEL should go OFF as soon as engine/crank starts to spin, that means computer is getting a good Timing Pulse from the EDIS-6 module, which means its getting a good timing pulse from Crank sensor
If CEL stays on then no timing pulse and no start

 

Ok, thank you for the message above I'll try that ASAP. My bad for mentioning the starter, starter selenoid, clutch position sensor that didn't have any relevance to my problem. I previously had a no-crank issue which I fixed.