Fuel pump?
 

Hey guys, I have a 98 F150 4.6, 138,000 mls, completely stock, and she won't start, here's the story she, sprang an oil leak about a yr ago, never could pinpoint where it was comin from so I parked her till I could come up with the cash to get it taken care of, she sit for about a year, at least once a month I would start her up drive around the block let it run for a few minutes. One day I needed to pick up some furniture, got there loaded it up, and it wouldn't start, would turn over but not start, called a wrecker, we had to push it out a parking spot so he could get in on the flatbed, was difficult to turn w/o p.s.the tow trucker said turn the ignition and it would make it easier to turn and when I did it started. Now fast forward a few months still parked, still go out and drive it a bit, go out a few weeks ago battery was dead, so I jumped it let it run drove it abit, parked it turned it off, decided to start it again to make sure, and same thing won't start, Where should I be looking?

When it won't start - check for spark and fuel - that's the usual place to start. Once you have isolated the cause as either fuel or spark, go from there. Don't start throwing parts at it until you have a plan.

My '99 4.2 v6 acted exactly the same way you have described - no start condition intermittently at first (spins over but won't fire, then the next day it starts fine) and then one day the problem is no longer intermittent. I agree to check the simpler stuff first but with your mileage I would say there's a good chance you're looking at a fuel pump. It's a pain - the tank has to be dropped and the pump ain't cheap - I ended up dropping just over a g-note when the tow, taxes, and labour were all added up. Hope you get back up and running cheaper than I did.

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It's relatively easy to confirm fuel, -

FUEL, -

A failed or failing fuel pump is the most common crank no start problem. This should be looked at first, it's like a bi-law. Determining, -

Since nothing has to come apart, this is also quick and easy, - Thread a pressure tester onto the shrader valve port located at the right side fuel rail and just above coil #3. Crank the engine to confirm pressure. Generally you want to see 32psi plus.

No pressure tester ? With the ignition keyed to the run position, crawl under the trucks fuel tank. Give the tank a few good wacks with your favorite blunt instrument (hammer). Since fuel pumps usually will begin to freeze up on their way out, this often wakes them up temporarily. You can usually hear them reawaken as they charge the fuel line with fuel/pressure. This procedure may also get the vehicle back home vs calling a wrecker.

SPARK, -

I figure most know how to determine spark, skipped..

Most common reason for a crank no spark issue with these trucks is a failed Crank Sensor hands down. A failed Cam Sensor would be #2. Check those first. :thumbsup:

It's the fuel pump. I almost guarantee it is. My '98 F150 would start fine the first start of the day. I would drive it somewhere, come back out after five minutes, and it would turn over but not start. I would let it sit 30 minutes or so and it would start.
I drove it up on ramps. A friend and I put a floor jack with a short length of 2x4 under the tank. Two straps holding the tank were easy to remove. Some posts say that the fuel pump is held in place with a retaining ring that screws around the collar of the pump. Mine was held in place by about six bolts. Make sure the tank is empty. You need the special tools to disconnect the fuel lines. Change the fuel filter while you're under the truck. The procedure is a bit of a pain. Not the worst thing I've ever done but not something I would want to do again. Still, with help and the right tools, you can do it. My friend and I are both 66. Getting back out from under the truck was the hardest part.

Also, I bought a nice fuel pressure test kit that had all the fittings I thought I would ever need. Guess what? The fuel pressure fitting for this model Ford is an oddball. Bought an adapter to make it work. Now the problem will be, if it was like mine, the fuel pump issue is intermittent. Some times it worked, some times it didn't. When it was working, the fuel pressure was fine. You have to catch it when it is not working to prove that it is the fuel pump. Good news is that after I changed the fuel pump, it is starting dependably now.
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This was my story -- https://www.f150forum.com/f6/turns-over-wont-start-428390/index2/

Same issue here, test for power multiple areas down the wire and all was testing out. I installed a Bocsh fuel pump lifetime warranty from auto zone and all to find out the wire going into the fuel pump was bad so I end up running a jumper wire the whole run. 275,000 4.6L 99 Ford XL