Crank-No start. No fuel. HELP! | Ford Explorer Forums - Serious Explorations

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Crank-No start. No fuel. HELP!

hal9000

New Member
Joined
February 18, 2006
Messages
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City, State
Flagstaff, AZ
Year, Model & Trim Level
'01 Ranger 4.0L 4x4
Morning all,

This morning my '01 4.0L ranger wouldn't start. It worked fine at 9pm last night when I drove home. I've narrowed it down to no fuel (no pressure at fuel rail). Here's what I've checked and found so far:

Inertia switch - OK
Fuel pump fuse - OK, 12V at fuse.
Fuel pump relay - OK, 12V on one pin with key off. With Key on, I'm getting 12V on 2 pins, and 6V on a third pin (sorry I don't know pin numbers). And with key on, I'm getting 6V at the inertia switch.

The only other item that might be worth considering is that it was about six degrees last night and is still in the very low teens, but honestly I don't think that's a factor.

Seems like I'm getting low voltage to the fuel pump. My only thoughts are either a bad ecu, or shorted fuel pump/fuel pump wiring.... But electric isn't my strong suit. I really need help on this, and hopefully soon.

I'm running in and out of my house trying to get my truck started so I can go to work, or at least drive the 12 mi to the closest auto parts store (I live out of town and alone) so please excuse if I don't respond right away.

Edit, I've also checked spark and am getting solid spark on crank, so it's def. not ignition related.
 



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Looks like your relay is bad. There are 5 pins in the fuel pump relay. With the key on, you should get 12 v on pins 2 and 3. Pin 1 will be grounded by the PCM for about 3 seconds to prime the system, then be grounded indefinitely once the engine catches on, until the engine is shut off. Pin 5 goes to a dark green wire with a yellow stripe directly to the inertia switch (and also spliced into the PCM). With a suspect relay you can jump pin 3 (light blue/orange stripe) to pin 5 to get the pump the 12 volts it needs. But you gotta pull the wire once you shut off the motor, so that the pump isn't running while it's sitting in the parking lot. It'll send all the fuel it's pumping back to the bottom of the fuel tank, but, really, you don't want it running with engine off.
 






Thanks for the response.

I should clarify that I was measuring voltage at the socket with the relay out. I found the label on the bottom of the relay and can confirm that at the socket with the key on, I have 12V on pins 2 and 3. But also have 6V on the socket for pin five (again, this is with the relay removed). I just made up a jumper switch and am heading out now to see if that will energize the pump, but I have my doubts.

Think I need to figure out why there's voltage on #5 with the relay out.
 






There's voltage on #5 with the relay out because there's voltage in the PCM itself. If you still don't have pressure after jumping 3 and 5, you have a pump or pressure regulator problem. I just got over one myself, mine was the regulator housing (plastic) which had many invisible stress cracks on it, causing 62 psi to be reduced to 17 psi, not enough for this system. If you're at 0, it's either the pump or the regulator housing. The regulator will last forever, it's made of stainless steel and is in my opinion indestructible, but it can get gummed up by varnish if the car hasn't run in a few years.
 
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No love jumpering #3 to #5 . going to try to reach the plug on top of the tank and jumper from there to see if the pump runs....
 












Just for clarity, you will only see 12v fuel pump priming voltage for the first 1-2 seconds after the key is turned on, it will remain constant only when the vehicle has started.

You should see >11v right after key is turned on, switching to the 6v you mentioned.

If you measure this the fuel pump is most likely shot.
 






Well, I finally remembered that I could turn the auto ranging on my voltmeter off and once I did that I was able to see that I'm getting that initial 1 sec flash of 12V to the pump before it drops down to 6V. I jumpered 12V to the pump again just to be sure (and smacked the tank a few times for good measure) and couldn't get the pump to run.

Guess I'm dropping my tank to pull the fuel pump and then biking to town for a replacement....
 






All fixed. Sadly the local dealership doesn't stock pumps, so I had to go with an aftermarket (airtex) unit. I guess I'll survive, and if it dies before its time at lesat I can console myself with the $400 price differential vs. what the dealership quoted me ($585 for a fuel pump?! Sheesh!)

Thanks for the assistance this morning. I really appreciated the extra input.
 






Glad you can drive to work tomorrow! :thumbsup:
 






The only other item that might be worth considering is that it was about six degrees last night and is still in the very low teens, but honestly I don't think that's a factor.

It could very well be.
I've heard that the springs that hold the fuel pump motor brushes retract when it's very cold so that the brushes don't contact.

The brushes have to be pretty worn out for this to happen.

Sometimes banging on the bottom of the fuel tank where the pump is will get it going for a while.

This is all hearsay, it's never that cold where I live.

From what I've heard on this forum is that the Airtex pump won't last much longer than 12 months.
Amazon has the original Bosch for $62.
At least you'll know how to do it next time. get a new fuel filter too.
 






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