I have a 2004 Ranger 4x4 XLT 4.0 V6 with auto trans that has run great since I purchased new in 2004.
So, now twice in the space of 3 months I have experienced what seems to be a vapor lock issue.
The vehicle has 151K miles & I don't drive it that much lately.
About three months ago I was at a store, I came out & the motor would not start. Everything sounded great except the engine sounded like it was not getting gasoline.
After about 30 minutes the motor finally started.
Fast forward three months, and today the same issue happened. I waited about an hour today, and finally got the motor started.
The symptoms seem to mimic a classic 'vapor lock' issue.

So, my question is: WHY after 16 years with absolutely no issues & 150K miles plus, would this vehicle have this issue within three months, not once but twice?
Very, very strange.
Is there some issue with this vehicles' gasoline line(s) being too close to some heat source, that after years of age, would tend to create such a scenario?
Many thanks for any tips!!

 

No to the vapor lock, that was a malady on older vehicles that used mechanical fuel pumps on the engine, so had 0psi or 5psi fuel pressure in the fuel lines, this allowed gasoline to "boil" if fuel lines got too hot near exhaust on a hot day, and fuel pump couldn't pump "vapor" just a liquid so engine stalled

Your fuel pressure is 60psi from gas tank to engine, so it would literally have to be in a HOT FIRE to "boil" gasoline under 60psi of pressure

It reads like your fuel pump could be failing
When you turn on the key LISTEN, you can hear the fuel pump in the gas tank run for 2 seconds, and only 2 seconds
Repeat key off and on as much as you need to, so you KNOW what it sounds like
"click", "HUMMMMMM" then quiet

Then next time there is a No start, listen

Its possible its the fuel pump relay in the engine fuse box, but long shot, you can swap it out if you want

 

Sounds like good information RonD

Thank you very much

 

Thanks again RonD; your information is very much appreciated!!
So, today I checked for the fuel pump '2 second' sound & the fuel pump is working.
I checked the fuel pump relay, which is seated properly, and I purchased a new relay.
So, my plan is this: Keep the new relay in the vehicle so, if the symptom happens again, which I'm sure it will happen again, I can change out the relay & see if that 'cures' the issue at the point of occurrence.
Will reply to the thread later to post updates.

 

Good stuff

There is nothing worse or harder to diagnose than an intermittent problem

I didn't mention it because it usually doesn't act the way you described, but a dirty fuel filter will cause lack of power or stalling issue but usually doesn't go away and come back
Fuel filter should be changed every 5 to 7 years, IMO, and they are not expensive just sometimes a pain to swap out, lol.

 

Hi RonD,
Yes, intermittent issues are a PITA
I change my fuel filter (and air filter) about every 20K to 25K; last fuel filter change was @ about 8K miles ago but that was also about 25 months ago.
Weird thing is I don't put many miles on this thing, like I used to so, I'm not sure how that may affect parts.
I will update the thread going forward so, hopefully if anyone else is having some similar issue, they may potentially learn from my issues.
Thanks again RonD!!

 

@RonD

The Ranger pulled it's **** again only 3 weeks after the second time.
This time, the 3rd time, the Ranger would not start even after waiting hours.
I tried the new fuel pump relay but that did absolutely nothing.
Had the Ranger towed to the shop & the fuel pump was DEAD; absolutely ZERO fuel pressure.
You nailed it RonD but the repair bill cost me out the ying yang
So, there ya go folks; RonD knows his stuff!!

While my Ranger was at the shop the techs found some other issues that I got repaired & the ole Ranger is a very happy Ranger, and I'm a very happy Ranger owner.

Cheers!!!!!

 

Thanks, but not happy it turned out that way

Yes, Motorcraft fuel pumps are expensive, but should last, my 1994 is still on original pump, knock on wood

 

I think the pressure valve thingy in my fuel pump is crapped out. I remember last winter you and I worked through my truck needing a long crank OR cycling the key one time before starting when it was cold as **** outside. You said there's a one way valve that's part of the fuel pump, and when the truck is off it's bleeding off the fuel pressure making it harder to start in bad weather. I've just ignored it this long, as long as its over like 35 or 40 degrees outside (9 months of the year in the midwest) it acts normal and you'd never even know.