Centennial!

It was a hot day here in Colo Spgs. I loaded the tuck to go camping ~ 800lbs and headed out. I spent 30 minutes in stop and go traffic before i got on the highway. Once on the highway heading up hill i was able to keep it at 50 -60 mph in 4th and 5th gear. 10 miles up the hill and 8500 feet, the truck missed a couple times then just quit. I let it cool off 30 minutes, it started up and we made it home. At first i suspected the high pressure fuel pump as it started whining a couple days ago , loud enough to hear over the engine. But, now im wondering if the stop and go led to a vapor lock. I have never had a vehicle vapor lock before so thought i would see what you guys have to say.

Thanks,

Chip

Steve83

EFIs can't vapor lock. The entire fuel system is under pressure, so there's nowhere for vapor to form. That only happens to carb engines, whose fuel pumps suck gas up from the tanks.

But there are MANY common problems with the 3-pump system, so it doesn't have to be the HP (frame) pump.

If you want more help, we need to see what truck you're talking about with each of your posts, so put ALL its details into your signature as this caption explains:


(phone app link)

Centennial!

Thanks Steve for the clarification re VL and, I updated my signature.
I suspect the HP frame only because of the whine it started to make recently and it was hot when i crawled underneath. After letting it cool, it drove home no issues but still whined. Could the HP pump overheat and not work properly?

Steve83

EFI fuel pumps are cooled by the fuel flowing through them. When you run it dry, it gets hot, and the impeller wears out RAPIDLY. If there's gas in the tank, and the pump gets hot, there's probably a fault in the fuel reservoir. Study this diagram, and follow the appropriate link in the caption:


(phone app link)

Centennial!

Thanks Steve.
To trouble shoot, should I check for flow going into the reservoir, leaving the HP fuel pump, and leaving the filter? Or, is a pressure check at the Schrader valve good enough?

Centennial!

Interesting, safety recall 89S76 has not been performed on my truck as it still has the fuel filter down stream from the high pressure pump. Could not find the recall on the Ford site or any recalls when i entered my VIN and there is no time limitation. If i take it to a dealership, im guessing they will laugh.

sdmartin65

Are you 100% sure the problem was fuel related and not engine cooling, maybe something as simple as the fan clutch not working properly. Im also at higher elevation with the 302 and mine reacts about like you describe if it gets to hot. It doesn't have to be so hot it's boiling into the overflow, just a a bit too hot and it will shut off and die.

Centennial!

Thanks Martin, Im not a 100% sure about anything with this truck. The temp gauge is always near the "N" in Normal. Sometimes towards the top and sometimes towards the bottom if im coming downhill. Seems consistent but that doesnt mean it's working right. When i opened the hood, nothing seemed abnormal WRT the radiator or overflow etc. When it quit, it was towards the top of the "N" but i have seen it there before with no issues.

I am 100% certain that the high pressure pump is whining and that is new. I took a pressure reading at the Schrader valve and it goes right to 40 psi when the pump primes the system. It idles at 35 and at 3000 RPM, its still at 35 psi. I believe that means the regulator and HP pump are working...? So, now im back to scratching my head. Maybe it's the low pressure pump and that cant keep the reservoir full enough for the HP to draw from over time and working. Im really easy on this truck. The other day was the first time i have had it loaded and working.

Thanks again, i really appreciate the help and ideas.

Steve83

You can call to see if any recalls are still open on that VIN. You used to be able to check online, but that function disappeared about a year ago. IDK if it has been reinstated...
http://www.fordparts.com/