2002 Ford Ranger intermittent starting.

[Ruttinbuck]

Thanks for your response, greatly appreciated

 

[lil_Blue_Ford]

It’s never happened when the vehicle is cold, only happens when I’ve driven awhile and shut it off for a few hours then go to restart its a mystery lol

This. I’ve been here.

My green 00 Ranger, when I got it, there was an intermittent no-start. Usually if you tried a couple times or cycled the key run-off-run-off a couple times it would go. Ran great when it ran and would always start cold. Replaced the fuel filter and chased down a few other things but no luck. Someone, I think it was @holyford86 told me to check fuel pressure. My retired mechanic neighbor brought his fuel pressure tester over and IIRC it was like 28 psi off and 22 psi running. The computers can adjust down to something like 16 or 18 psi running, but starting when it’s warm with that low of pressure it vaporizes fuel in the rail. It’s a little less of an issue with the old return system because a couple primes and you push new fuel into the rail and the vapors into the return line back to the tank, but the returnless, well…

New fuel pump and it was good to go. So despite a lot of hearing that a pump either works or doesn’t, well, weak pumps happen. As it is, my mom’s 02 Explorer (4.0 SOHC) started doing the same thing. I had bought my own pressure tester at that point and same deal, weak pump. Replaced it, was fine for like two months and same problem. First thought was it can’t be the pump. Fuel pressure test showed that was a lie, it was the pump. Again. Replaced again and it’s been fine. Think I used an Airtex in mine and a Delphi the first time in moms, not sure what the second pump for hers was. Don’t quote me though, that was a few years and two concussions ago

 

[Ruttinbuck]

I was hoping it wasn’t the pump, but that seem logical. Should have an opening in the box so you don’t have to drop the tank. Lol thanks much appreciated

 

[holyford86]

I was hoping it wasn’t the pump, but that seem logical. Should have an opening in the box so you don’t have to drop the tank. Lol thanks much appreciated

It could also be a fuel injector leaking down, if you hold the gas pedal all the way to the floor while cranking, it should not fire or try to start at all. If it does, that could also be an issue. Pulling the bed is easier than dropping the tank usually, but I see you're in the land of the road salt so that could be a fun adventure, haha

 

[Ruttinbuck]

I’ve tried holding the gas pedal all the way down and it didn’t start, couple quick on and off with the switch and started right up. Haha your right about the salt it’s challenging trying to do anything on the vehicle, and I oil mine every fall, can’t imagine what it would be like if I didn’t. Lol

 

[RonD]

Ford has the fuel pump come on for just 2 seconds with Key on, to prime the fuel system, that adds about 10psi of pressure to what was already there, fuel pump doesn't come on again until engine RPMs are above 400(cranking speed is 200rpm)
Fuel system should hold pressure for MONTHS when vehicle sits

The 1997 and earlier fuel system ran at 35psi, so if fuel system was bleeding off pressure when it sat, the 10psi would usually get engine to start and maybe stall just after starting, but pump would have come on briefly(RPMs over 400) so engine should restart easily

1998 and up run 60psi pressure, so that 2 second run time should have been changed to 4 or 5 seconds, in my opinion
In any case if fuel pressure did bleed off the 10psi wouldn't be enough for a startup
So cycling the key on and off 2 or 3 times, would get pressure up to 20-30psi and enough for a start up

Why the 2 second thing?
Safety
If there was an accident or roll over and a Fuel Line broke, the electric fuel pump would just keep pumping out fuel as long as the key was on and battery was connected
But if a fuel line broke the engine would stall, under 400rpms, so fuel pump would shut off, couldn't feed a FIRE
There is also an inertia switch that can cut power to fuel pump

Since the advent of electric fuel pumps in consumer vehicles there has always been an engine off power cut for these pumps
In carb engines it was an oil pressure switch, no oil pressure and no electric fuel pump
Carbs have a float bowl so have gasoline on hand to start the engine, so not having the pump come on with key on didn't matter
Fuel injection doesn't have that option

 

[Ruttinbuck]

Thank you for the explanation, mine must be leaking down when that happens then. It’s been doing that for 8 years or more and very sporatic , maybe a new fuel pump in the near future. Thanks again much appreciated

 

[lil_Blue_Ford]

Arguably, pulling the bed is the easiest way to deal with the pump. Disconnect the taillight harness behind the bumper, pull the three bolts holding the fuel filler neck, pull the 6 bed bolts. Pick the bed up and slide it back. It’s possible to just slide it back and not completely remove it from the truck. Thought about cutting a hole in the bed, but where the pump is, it’s not really a practical solution.

There is a fuel pressure regulator on these newer “returnless“ systems, but it’s part of the fuel pump sender assembly. It is possible that the regulator is bad and not the pump, but you have to pull the pump to get to it and that presents the issue then of having to test what’s actually wrong. IMHO, easier to just throw a new pump on and be done with it.

FYI, I believe it’s Dorman that makes replacement bed bolts and clips, it’s cheaper than going through Ford. I’ve also put 1/2” weld nuts in the frame and grade 8 bolts.

 

[Eddo Rogue]

Leaky fuel injectors flooding the engine?

Next time it happens hold the gas pedal all the way to the floor and crank the engine over, that'll kill the injectors, if it still fires up with the pedal all the way on the floor then you have an issue with injectors.

or

Next time it happens pop the hood and check the fuel pressure if you think it is an issue with the fuel pump. Doesn't really sound like a fuel pump to me.

I must do this sometimes to start my ranger. She wont start unless I push pedal while cranking. I replaced the injectors when I did the lower intake gasket. I bought some mid priced ones from rock auto. I still have the originals but they need to be cleaned. Maybe I will do this and swap em. Ironically fires right up when cold, its the restarts after that require pedal.

 

[Ruttinbuck]

Arguably, pulling the bed is the easiest way to deal with the pump. Disconnect the taillight harness behind the bumper, pull the three bolts holding the fuel filler neck, pull the 6 bed bolts. Pick the bed up and slide it back. It’s possible to just slide it back and not completely remove it from the truck. Thought about cutting a hole in the bed, but where the pump is, it’s not really a practical solution.

There is a fuel pressure regulator on these newer “returnless“ systems, but it’s part of the fuel pump sender assembly. It is possible that the regulator is bad and not the pump, but you have to pull the pump to get to it and that presents the issue then of having to test what’s actually wrong. IMHO, easier to just throw a new pump on and be done with it.

FYI, I believe it’s Dorman that makes replacement bed bolts and clips, it’s cheaper than going through Ford. I’ve also put 1/2” weld nuts in the frame and grade 8 bolts.

 

[Ruttinbuck]

I also thought about a hole in the box also but it doesn’t line up with the sending unit. When I change the pump I will definitely try the shifting the box back a bit , if the bolts come out. I have undercoated with used oil every year so they might not be too bad. Thanks for your reply

 

[lil_Blue_Ford]

I also thought about a hole in the box also but it doesn’t line up with the sending unit. When I change the pump I will definitely try the shifting the box back a bit , if the bolts come out. I have undercoated with used oil every year so they might not be too bad. Thanks for your reply

Some vehicles you can get away with making an access hole (Bronco II), but where the pump is at in a Ranger, it’s too close to the front of the box. You need about 2’ of room to work on the pump, but that can be achieved with the bed balanced on the rear tires and back bumper. With the tailgate off, the bed is nose heavy enough that it stays put just fine.

 

[Ruttinbuck]

I also thought about a hole in the box also but it doesn’t line up with the sending unit. When I change the pump I will definitely try the shifting the box back a bit , if the bolts come out. I have undercoated with used oil every year so they might not be too bad. Thanks for your reply

Good to know! Thanks much appreciated

 

[Ruttinbuck]

i would just like to say, I’m glad I found this site, you guy’s are great. Before I found this site I tried posting on different sites and never got a response to any of my questions. The help I got here has been overwhelming, just want to say thanks to everyone.