Started fine, died on idle/under throttle. Then worked fine later.
 

Hi guys,

New to the forum as I'm a somewhat new owner of a 2003 V8 F150. Around 230k on the odometer. I bought it last July from an older gentleman, single owner, extremely well maintained.

It's become my work truck and DD and so far has given me almost no issues. Today that changed.

I'd just driven about 60 miles to pick up a large load of building materials (maybe 800lbs on my ladder rack). Drive was totally uneventful. All gauges fine, everything felt and sounded normal aside from the added wind noise from the load. Backed in to unload the rack and turned the truck off.

When I went to drive away it fired up just fine but seemed to sputter a bit. I put it in gear and gave it some gas. Nothing. Didn't move and RPM's didn't rise. I tried that for a while longer and it died. Tried a few more times, everything it started right up, everytime I attempted a bit of throttle and it would stall out. Each time I tried it was quicker to stall out then previous attempts. Eventually (after perhaps 5-6 attempts) it still started fine but stalled out quickly without any throttle at all.

That was about 1pm. I left it where it was and figured I'd start researching this evening. Around 6pm I took my other vehicle to where it was parked (had to retrieve some items) and out of curiosity started it. No issues at all. Everything appears normal again. I didn't drive it home because I needed to get my other vehicle back but drove it around a bit without issue. I've yet to find this scenario so apologies if the answer is there and I missed it.

Any ideas or input are super appreciated.

Thanks,
Evan

Sounds like a possible fuel pump failure.... they usually fire a couple warning shots when they get hot, then just die.

Hmm, that could make some sense. Would it really manifest like that, though? I'd sort of expect it to have acted up before the truck was shut off. It would presumably be just as hot as I was parking it.

Is there a way to diagnose/check the fuel pump or should I simply replace it and see how it goes from there? I was almost unhappy that it started up and ran normally. Now until I figure it out, it will be hard to trust it.

I will bet on it being the fuel pump. Check my posts about my problems until I finally changed the fuel pump. Runs, starts fine now. Change the fuel filter too while you're at it.

This was my story -- https://www.f150forum.com/f6/turns-over-wont-start-428390/index2/

You can't trust it. It's intermittent, sometimes with no warning. There's nothing like going to the tire dealer to buy four new ones only to have the truck fail to start when it's time to put them on. Then you watch the poor young tire changers roll floor jacks into the parking lot to change the tires.

Yep!

Thanks for the input, everyone. I'll be ordering a new pump and filter this evening. I had my share of intermittent issues with the alternator on my Land Cruiser was starting to go. Worked just enough to convince me it may be something else, until it didn't.

Anyone have any insight into how quickly the pump will totally die now that I've had the first issue? Just curious if driving it the next couple days is not a huge concern, is a medium concern, or is a totally horrible Idea? I could make do without it and move my work tools over to the Cruiser but the Cruiser can't pull the trailers.

Thanks!
-Evan

Depends on the weather.... if it is cold where you are, you'll probably get a little more time. The pumps don't like heat. Don't fill your tank all the way up, or it will die right then (karma, lol).

Serious though, it goes against the grain in keeping the pump cool, but you don't want to be handling a full tank. I'd keep it at no more than a 1/4 tank - drive something else if you can.

Interesting. Some of what I read about pump issues were solved by keeping it full. I can see it overheating more easily that way though. It was right around a quarter tank when it wouldn't start.

I'm in Boise, Idaho. Average daytime temps right now are 40-45 or so. I'll def be sticking with my Cruiser as much as I can until the parts show. I can get them locally but heck if the shops don't want like 80 bucks more than Rockauto for the same thing.

Another question: any particular brand of pump that's better than others? Prices kinda seem all over the place but reviews of some of the lower priced ones all seem decent. I'm not against spending money when it's needed but usually have a hard time deciding when it is. Thoughts?

Thanks!