Hello, so my current 1994 Ranger will crank with no start. I parked it one day, and it just wouldn't crank after. Occasionally it would roll over and run fine until parked again, only to repeat the same process. Now it wont roll over at all. I suspected it to be a fuel issue. I have changed the fuel pump after not hearing it run thinking this had to be the problem. It was not, so I checked for spark. I had spark then sprayed carb fluid into intake and truck fired up attempting to start. So I checked all fuses, relays, and inertia switch. fuses were fine, inertia wasn't tripped. But the Relay for the fuel pump wasn't clicking on even changing the relays out. so now I'm stumped. Wiring looks fine I'm getting the 12 volts to the relay but nothing to fuel pump. Not sure if it helps, but I even direct wired the fuel pump from the battery just to double check the pump to see if it was faulty even tried cranking the truck that way with still no success. I see where some people say it could be an ECM issue just curious if anyone could help me out before I drop more cash. Thank you!

 

Welcome to the forum

You did the 50/50 test
Sprayed fuel into the intake and engine started but died, so spark is working and timed correctly, but no fuel is getting in from injectors

You say you "jumped" power to fuel pump, but you never said if you heard fuel pump running?
If you didn't hear it running then you got a bad "new" fuel pump, it happens, unless its a Motorcraft pump

If you did hear it running then you are down to fuel filter or fuel injectors
Filter could be clogged, its in the frame rail under drivers seat area

Unplug the TPS(throttle position sensor)'s 3 wire connector, its on the throttle body across from the throttle cable linkage
If TPS shorts out, fuel injectors will be turned OFF


Just FYI for 1994 and earlier Rangers
You can activate the fuel pump relay manually, look here: https://www.therangerstation.com/tec...ry/OBD_I.shtml
second drawing shows the OBD1 connector in engine bay, found on drivers side of engine bay between fuse box and firewall
The Fuel Pump(FP) slot is labelled, this is the GROUND wire that activates the FP relay, computer pin 22 grounds this wire if its working
So you can use a jumper wire from this slot to a Ground
When key is on FP Relay should close and fuel pump will run, if its working, full time, until key is turn off

 

Thank you for the reply so quickly!
So yes the fuel pump did kick on, and I did forget to mention previously that when I changed the pump I also replaced fuel filter.
I will look into your advice about the TPS and activating the relay manually this afternoon at work currently.

 

All fuel injection computers have a "Clear Flooded Engine" routine built in
I use mine every morning

Key on
Press gas pedal down to the floor and hold it down all the way<< this tells computer to shut OFF fuel injectors
Crank engine
It should NOT start, it should not Fire at all

When you release the gas pedal the computer will start up injectors, even while still cranking

TPS is used for this
Computer sends TPS 5volts with key ON
When throttle is closed, TPS sends back .69 to .99v, so under 1volt
When throttle is wide open(WOT) TPS sends back 4.5-4.8volts

If RPMs are 0, and TPS is 4.5v or higher(gas pedal to the floor), computer turns off fuel injectors for "Clear Flooded Engine" routine

So if TPS is shorted it could cause no fuel injectors while cranking, long shot to be sure but not a no shot, lol

I use it every morning for my high mile 4.0l, almost 400k
I crank the engine over for a few seconds to get oil pumped up thru the engine BEFORE I let it start up