I hope I'm posting this in the right forum. I've been having trouble off and on for more than six months with my 1999 Ford F150. I'll be running smoothly(I'm a newspaper photographer so I stop and go with my truck a lot) and I'll stop to take a picture and about 10-15 minutes later I go to start the truck but it won't start. The battery works and it acts like it's going to start but then the truck rumbles, shakes and tries to start but then finally fails. Usually if I leave it 30+ minutes just sitting there it'll finally start fine.

I took it to a local mechanic a few months ago but they couldn't get the problem to replicate. They tested the fuel pump and said it was working correctly. They told me to have it towed the next time it messed up. So a few weeks later it messed up and I had it towed. When it arrived at the mechanic's place, you guessed it, it started right up.

Until today it hasn't messed up on me for about two or three months. But it could go a week or two without failing to start. We've changed the fuses in the fuse box and that didn't help. Today I noticed when I turned on the truck(before cranking it) the fuel pump didn't seem to start but made a gurgling noise about 3 seconds after turning the car's power on(not cranking it). I don't think it's the battery because it starts it just won't stay cranked after the initial "vroom." It seems like it's the fuel pump but the mechanic tested the pressure and said it was fine, so I really don't know. I'm not good at all with vehicles so any help here would be much appreciated!

Edit: I forgot to mention there are no codes that it shows. A while back it was showing p0122 p1120 p1121 but after a few minor repairs followed by a code reset the codes haven't returned.

 

When was the last time you changed the fuel filter?

 

I'm not sure when the last time was. I don't think I have. Another thing I noticed it does(and it did this several months ago but began working fine again until now) is when I'm driving and give the engine gas, the RPMs don't go up. I hear the engine trying to rev up but it doesn't. The speed doesn't increase either. I can put the pedal to the floor but it doesn't give me more than a couple thousand RPMs. Then when I back off and try it again, it works. I'm starting to think the issues are related. I've put seafoam in the gas tank within the last six months but it didn't help. Thanks for your input!

 

The fuel filter needs to be changed every 30k. Change it.

 

Ok, I'll change it. I took the truck to the shop and they changed the TPS and that helped with the acceleration lagging. But I still had a problem the other day with it not cranking. I saw on another post somewhere to hit the fuel tank a few times with a rubber mallet and try to crank it. I did and it fired right up. I've never gotten it to crank like that without letting it sit for a long time. Does that point to a fuel pump problem? And could it be that intermittent of a problem? Thanks for your help!

 

If it, the fuel pump doesn't run properly when you first turn the key to ign, pull the tank and replace it, while also cleaning out the inside of the tank of muck if you find it there. Sometimes/most times the fuel pick up gets nasty. I would offer test the fuel pressure but you have had the problem to long to worry about that.

 

redacted

 

This may not apply to your year of truck but on my 2013, the 20 amp fuse for the fuel pump (the fuse box that is above the radiator in front of the engine) is a known issue.

It draws so much current that it actually gets hot and kind of melts the plastic around the sides of the fuse, which interferes with the connection. The fuse isn't blown... its just not making contact. Sometimes it makes contact, sometimes it doesn't. So it's it's intermittent crank-but-no-start problem. If you take that fuse out and scrape the sides of the fuse with a knife and put it back it, it will work for another 5000 miles or so. Or just replace the fuse with a new one as needed.

I guarantee if I would have figured this out I would have taken it to a shop, they would have replaced the fuel pump, ($1000) and then when the new fuel pump didn't work they would have tracked it down to the fuse. ($1). And they would have changed the fuel pump for nothing. But wouldn't have told me about the fuse. "Yep, it was a bad fuel pump!"

Edit, sorry for the reply on the old thread. Fifty150s reply threw me off.