98 Explorer--- Not Hearing Fuel Pump Whine When Key is turned- No Start

[Sal]

1998 Explorer with 5.0L V8. Ran in to a intermittent crank but no start situation. 144k miles.

I noticed that when I turn the key on, I don't hear the fuel pump whine whenever the no-start situation occurs.
Fuel pump was replaced 14 months ago along with filter. When engine runs the fuel pump is quiet and motor runs fine..
I already swapped the fuel pump & PCM replays.
I also checked the inertia switch to make sure it wasn't tripped. I also checked the 20A & 30A fuse located in the engine compartment fuse box behind battery, they were all fine.

I noticed its been usually starting fine when it is cold but if I shut it off and try to restart it 15 minutes later, I won't hear the fuel pump whine and it won't start.
Twice it restarted after I let it sit for a while but a short while later it stalls out.
About 4 hours ago I shut it off after a 1 mile ride from a cold start. I tried to restart it after 15 minutes of sitting and it wouldn't. I just tried again after 4 hours and still no luck. Fuel pump hasn't whined with key on.

I thought for sure the problem was the PCM relay but I was wrong.
Any ideas?

 

[Sal]

UPDATE: I smacked the gas tank a few times with a rubber mallet and it started up. Fuel pump?

 

[poker4me007]

UPDATE: I smacked the gas tank a few times with a rubber mallet and it started up. Fuel pump?

Yep! Probably!

 

[koda2000]

Fuel pump with 99.8% certainty. What brand of fuel pump did you install last time? I only recommend Bosch brand replacement pumps.

 

[IronCurtain]

Yep, I replaced the pump on my 95 with a cheapo, and it died days later. Replaced with another cheapo and it died within a couple weeks. Bought a good one, I keep my gas above 1/4 tank and I haven't had a problem in a couple months.

 

[Mbrooks420]

Get a better pump. I run my tank to the bottom every single time, and get the same pump lifespan as everyone else. I don’t believe there is any truth to running it low, and “overheating” the pump.

 

[koda2000]

The first pump I changed was with an AirTex pump. Not particularly cheap, but it only lasted about 1 year/10k. I've been installing Bosch pumps (6-7 of them over the past 6-7 years) in all my Expl's and Monty's with no issues. I swear by Bosch pumps, but Carter pumps are also a good choice and were OE IIRC.

 

[Sal]

I checked fuel pump pressure at the rail at idle = 34psi.
Of course the only way to get the pump going is with a few wacks of the rubber mallet on the gas tank.

 

[koda2000]

If the fuel pump doesn't run on it's own the fuel pressure it makes when it does run is irrelevant.

 

[MrQ]

Better quality fuel pumps can last years. I just took one out that was 5 years old and still running strong, wound up replacing it with another because the sending unit was bad (cheaper that way). Fuel stabilizer is paramount if it's going to sit for a while, however. Unfortunately, if you let the Explorer sit with gas in the tank for a protracted period of time (a month or more) the ethanol starts destroying the pump. I have replaced so many of these damn things, I could make a career out of it.

 

[IronCurtain]

Actually come to think of it mine sat for 2 months when the 2nd pump died. That's probably why it did then hmm.