30 second run time then dies, must wait (hour?) before it will restart

[freak]

2000 XLS 4.0 OHV. I have replaced the fuel pump maybe 100K miles ago with an autozone pump I believe. The car has been running great for ages. I left it sit for 4 days while I was on vacation. I came home and it started right up. Drove about 2 miles and shut it off. Came back in 30 minutes and it would only crank. Cranked well though. Came back the next day and it started right up but will only run for about 30 seconds. Then it won't start, only crank. Let it sit for an hour or more and it will start and give you another 30 seconds. My fuel pressure test gauge won't fit this car but I have one on order due to arrive wednesday. How would I tell fuel pump vs fuel filter?

 

[Mbrooks420]

Replace the filter and retest pressure.

 

[EB4X]

Autozone loans out fuel pressure kits for free....pay deposit, get full refund when returned. So you can test tomorrow instead of Wed. Fuel filters almost always cause sputtering symptoms initially, sounds like your pumps going out, common symptoms, starts one moment, not the next. 100K for mediocre brand is likely standard lifespan. You could always spray some carb/ injector cleaner..starter fluid in intake....if it starts consistently each time with that - fuel pump.

 

[freak]

Autozone loans out fuel pressure kits for free....pay deposit, get full refund when returned. So you can test tomorrow instead of Wed. Fuel filters almost always cause sputtering symptoms initially, sounds like your pumps going out, common symptoms, starts one moment, not the next. 100K for mediocre brand is likely standard lifespan. You could always spray some carb/ injector cleaner..starter fluid in intake....if it starts consistently each time with that - fuel pump.

What brand pump do you recommend?

 

[donalds]

Sounds like a clogged filter

 

[C420sailor]

My truck did the exact same thing and it was the crankshaft position sensor.

 

[EB4X]

If no codes...which I assume is the case, do the aforementioned spraying of injector cleaner / starting fluid in the intake...
Carter fuel pumps are good, made in USA........or at least were last time I checked...have one in mine and doing well.
**CHECK your VIN to see if your Explorer is USA or Mexico assembled...they take DIFFERENT units....may not be an issue with your 2000 but in earlier 2nd gens like mine it was.

 

[yeahokay]

Test fuel pressure first, if not good replace filter, test again if not good replace pump. If fuel pressure is good I’d look for restrictions on air. idle air control valve can cause this as well but generally that is more starts up then dies immediately.

 

[freak]

Update: Truck starts up. Fuel pressure reads 60+ psi. Runs, dies, never drops below 60.

 

[EB4X]

Do a scan over of engine vacuum lines...make sure none popped off / loose......overall wiring look good? ...no critters got under hood while you were away and did chewing? check air filter too... when a vehicle sits they like to make nests in air filters... granted long shot especially being it only sat for 4 days...but....

 

[Turdle]

My truck did the exact same thing and it was the crankshaft position sensor.

This is where I would look next. I believe the check engine light will tell you if the sensor is working.

 

[Turdle]

How to: - Ford Explorer Engine No Start Procedure

This procedure diagnoses a No Start engine problem. The procedure is based on information from the Ford Service Manual and my personal experience. The numbered steps should be performed in the order listed. 1. Does "THEFT" blink rapidly with ignition key in Off, On or Start? Yes: Verify key...

www.explorerforum.com

 

[freak]

Update: No spark.

 

[Turdle]

Update: No spark.

Step six in procedure above

 

[freak]

Check engine is on (maybe slightly pulsing) while cranking.

 

[Turdle]

It's kinda tricky, but try disconnecting the crank sensor, tap on it with a tool, then plug it back in.

Sounds silly but if it snaps the truck to life you'll know it's a bad sensor. It appears to not be sending a strong signal.


If it were more intermittent a wiring check would be a good idea, but since temperature or use seems to disable the vehicle I think the sensor is faulty. Good call @C420sailor

 

[EB4X]

Just an FYI, if it is the crank sensor, on our 4.0ohv engines, the serpentine belt is just a bit in the way of removing the crk sensor bolt, from bottom of vehicle by yourself, you can access tensioner / loosen the belt....just slide it off the harmonic balancer leaving the rest of belt IN PLACE....then just as easy put back on from bottom.

 

[freak]

Just an FYI, if it is the crank sensor, on our 4.0ohv engines, the serpentine belt is just a bit in the way of removing the crk sensor bolt, from bottom of vehicle by yourself, you can access tensioner / loosen the belt....just slide it off the harmonic balancer leaving the rest of belt IN PLACE....then just as easy put back on from bottom.

Thanks appreciate that!

 

[freak]

Running out of time tonight but went under and wiggled the connector. Didn't take it off. Started up and stayed running. It kind of bothers me though because that makes me feel like it could be a wiring issue instead of the sensor. I'll run it longer tomorrow to do a better test.

 

[Turdle]

Idea.
Make a note of check engine light behavior during cranking