Hi Guys,
I have a 2002 Ranger with the 4.0, 4x4. I was driving a couple days ago at 55 mph and my truck shut down. I pulled off the road and finally got it started back. Once it started back up, it ran fine, and I drove it about 5 miles back home. Now when I start it up it idles fine, but when I put it in gear, it starts to run rough. I checked the fuel pressure while idling and it reads 60 psi, but it idles fine. Any ideas???

 

Changed the fuel filter lately?

 

Welcome to the forum

60-70psi is expected fuel pressure while running, but real test is to shut off the key and see if system can hold pressure, above 40psi for a few months, you don't have to test it that long, lol, 10 minutes is fine.

Any other symptoms when it died?
Did it stumble a bit or just die like key was shut off?
Did CEL come on, did dash lights stay on, i.e. oil light and/or battery light came on when engine stopped?
Did anti-theft light flash faster?


"finally got it started back up"
How long before it did started back up, 5min, 30min?

Did you hear the fuel pump come on for 2 seconds each time key was turned on?
It should, it isn't quiet.


There are only a couple of things that can cause engine to stop while driving.
Fuel being shut off
Spark being shut off
Crank position sensor shutting off(shuts off fuel and spark)
Computer shutting off

Fuel pump power is controlled by the computer via the fuel pump relay, it is in the engine fuse box, $6-$8 part, some replace it on spec. after a shut down like you had.

Fuel pumps do quit suddenly, and don't restart right away, could be yours is wearing out.
Listening for it to come on now, for 2 seconds, while it is working, will be helpful if engine quits again, then you know what to listen for.

Spark is pretty bullet proof on 1996 and up Rangers, and you have 3 coils in that one coil pack, so losing all 3 at the same time would be unlikely.
Coil could lose power but I doubt it would just come back on after sitting.

CKP(crank position) sensor is behind the crank pulley, they rarely fail and when they do they don't usually start working again.
CKP sensor reads a "tone wheel", looks like a gear, each tooth on that "gear" cause CKP to send a pulse to the computer.
CKP sensor pulse "tells" the computer the crank is turning so computer needs to start spark and fuel, no CKP pulse means shut off spark and fuel.

Computer shutting down would of course shut off fuel and spark, but it is unlikely engine would restart with computer failure.


If you get a spray can of Quick Start(ether), then IF engine shuts down again, you can remove power brake hose and spray some into the intake, replace hose and try to start engine.
If engine starts then dies, fuel is the problem.
If engine still doesn't start then spark is the problem

 

Thanks guys for the responses. Just checked on the Ranger and it is still holding 35 psi from a day and a half ago. I fired it up and drove it around the neighborhood for a few minutes and it ran fine, as if nothing is wrong. I'm wondering is my fuel pump playing games with me. There are no check engine lights on. When it shut off while driving a couple days ago, it was all of a sudden with no warning. I guess the only thing I can do is drive it until it happens again...

 

35psi is fine

If fuel pump relay was the problem you would usually get a CEL and code.
Computer turns on the relay and monitors the voltage going to the fuel pump, if relay suddenly opened, computer would see power go off and report that with a code and CEL.

Listen for the fuel pump running when key is turned on now, so if it does happen again you can tell if thats the problem.

Fuel pump motor is cooled by the fuel in the tank, it has a thermal limiter on it that can shut the pump off if it gets too hot, was the fuel level low when engine shut down?

After cooling off it would start working again, this would be a sign pump needs to be replaced.

 

I think I found the problem. There was a small insect that somehow got stuck to the MAF sensor wire. I took the sensor out and cleaned it and all is well, so far... Now I need to find out how he got in there. Thanks again for the help.

 

Thanks for the update

Good work finding that issue.

Very odd about the stall though, engine should continue to run with bad MAF sensor data, you would just get CEL

 

I am going t'through a similar problem. The truck would run for a while then shut off. If I waited five minutes it would start again. The repair was to replace the fuel pump, which was done. I picked it up, drove it for 7 miles, and it started doing it again! Any ideas?

 

Inside the cab in passenger foot well you will find the inertia switch, can also be behind kick panel on that side, depends on the year.
Inertia switch passes voltage from fuel pump relay to the fuel pump

Google: Ford Ranger inertia switch image

So you know what to look for

Connect a volt meter or test light to either terminal on inertia switch and a Ground.
Turn on key, you show see 12volts for 2 seconds then no or low voltage(6volts), depends on year.
Now start engine, go for a drive, if engine stalls and you still have voltage to fuel pump then it isn't a fuel pump power issue