Hello to everybody - New to this site. Have been lurking around a bit and it looks like a lot of good information here...I have a question about something my 2001 F250 Super Duty V10 has started doing. First, a bit about the truck to hopefully answer any questions that might come up in the diagnosis of the problem I've begun having...I bought the truck in May of 2017, with 115,000 miles on it. It was and is still in beautiful condition, both inside and out. It's an automatic 2 wheel drive 4 door crew cab. I maintain all of my vehicles and have done so with this one as well, with all normal maintenance on a schedule. I also know my way around most all of the working systems of any cars or trucks, so I am by no means a novice - not a professional mechanic either, but I can normally fix most anything and have the tools to do it. OK...after all of that - the truck has been absolutely 100% reliable since the day I got it. It now has 149,000 on it and has never skipped a beat in any way. In 3 years, I have logged about 35,000 miles on it, so it's obvious that I don't use it all the time. Many times it sits in the driveway for 2 or 3 weeks without moving. I am in the Southeast, so we don't have any kind of severe weather, other than it gets hot in the Summer time. No snow or anything like that. During those times of it sitting, I do go out and fire it up and let it run for 15 or 20 minutes at a time, to keep the battery good and keep it loosened up in general. Here is where the problem started...It had sat for probably 2 weeks since I had started it. I went out to start it, per my normal routine and it just turned over and over for 10 or 15 seconds without firing. I had never experienced that with it. It always fires right up, but not this time. I tried it several more times (the starting was very strong since it has an almost new battery) and got the same result - just turned over and over and over. So I left it for a while to think about what in the world could have happened with it just sitting there. Everything under the hood was clean and in good shape, just as always, no surprises there. Anyway, I got the thought to get some starter fluid that I keep around for other things and try that. Took the air duct loose at the filter and shot a couple of seconds worth of the ether up in it and it stumbled just a second and then fired up. I put the duct assembly back together and let it run for the usual 15 to 20 minutes. It ran perfectly smooth and did nothing out of the ordinary. So then I started to experiment with it a little to see if it would do it again. I let it sit until the next day and tried it again - fired right up like it always has. So I let it sit for 2 days and tried it again - same result, fired right up as it normally does. So then I began to think it was just one of those quirky things that occasionally happens with any vehicle and can just be filed under the "I don't know what happened, but it works fine now" file - almost always a mistake. Anyway, after 3 or 4 days of sitting, it did it again. I did the same procedure with the starting fluid and it fired up again. It has now done this 3 times in the last month, so it's quite obviously something that isn't going to go away without some fixing. I began to think that maybe it was the fuel pump but that makes no sense since it runs and drives fine after getting it started. The other air induction pieces seem to work fine after getting it started. A throttle position sensor problem didn't sound right either, again, since it runs fine after getting it started. A mechanic friend suggested cleaning the throttle body, which I have no problem doing, but I don't see how that could cause this problem. I'm so far at a loss...has anybody had a similar thing happen to their V10? It may be something common and easily remedied that I've just never heard of or maybe something worse? From the way it has played out so far, I don't believe it to be anything that's a big deal. Any advice would be greatly appreciated!
Sorry to be so long winded but wanted to describe the truck and it's problem as best as I could...

 

Since it starts and runs fine once started, but need some fuel to get it started, how about we try this.?
As you know the fuel pump runs for usually 2-3 seconds when you first turn the key on, listen for that each time you go to start the engine. When it won't start listen if you hear that fuel pump run when you first turn the key on.
Let us know if you notice anything different.
A little suspicious of fuel pump driver module.

 

OK, that sounds logical. I'm not familiar with the fuel pump set up on this truck other than to know it is on top of the fuel tank and I really hope that's not what is ailing it. That looks and sounds like a real pain in the butt to even get to, plus the price for them is fairly well ridiculous, as are most things now. When you mention the driver module, what exactly is that and where is it located? I can certainly look around the internet and find it but it sounds like you've been der dun dat, so it would be easier and quicker for you to let me know, if you don't mind...

 

I believe on your particular vehicle it is mounted in front of the fuel tank, on the passenger side.
Might be a good idea to google it so you can get an image to see what you are looking for.
Some older vehicles had a problem with corrosion developing at the mounting between the driver module and the metal of the vehicle.