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Ford Explorer Stalling Mechanic is Stumped

Curious if anyone has any ideas. I have a 2002 Ford Explorer Limited with almost 180,000 miles replaced the original fuel pump around 150k the replacement pump failed almost immediately and we replaced it again that pump started showing signs of having issues (stalling out around 1/4 tank etc…) about a month ago we replaced the pump again. The truck is now having bizarre symptoms in stitutions where I have been driving continuously for more than about an hour the exterior temperature reading on the AC will read 50 degrees (the exterior temperature is in excess of 100) usually with in a few minutes of that the car will start stalling … there is no check engine light or codes we have had it hooked to a scanner and it will indicate it’s not getting enough fuel once it starts stalling but all the readings are great up to that point same with fuel pressure. Once the car has been off for about ten minutes it will start back up again like nothing ever happened. We have tried switching out the relay but that hasn’t solved the issue. I do think possibly the fuel economy has been lower than usual as well but am not 100% sure.Does anyone have any clue?

Has the fuel filter been replaced?

Are both heat baffles over the fuel filter still in place?:

Doesn’t the fact that the temp readings go haywire before the stalling suggest a problem with one of the computers? I don’t know any more so I’ll shut up but something must be wacky.

This sounds exactly like an evaporative emissions system problem. If the fuel tank is unable to breath in as the fuel is used up, a vacuum develops in the tank that can result in the pump being unable to draw the gas. The next time you have the problem, try removing and reinstalling the gas cap as a test. If the problem disappears, that’ll confirm my suspicion.
Have you had any fault codes? If so, what are they?

The tank breaths in and out through the vehicle’s carbon canister. If the canister’s carbon bed is saturated, it will prevent the passage of air and can cause the problem. Failure of the purge system can allow the carbon bed to become saturated, and “topping off” at the pump can cause saturation. If you “top off”, I recommend discontinuing the practice.

Note that the aforementioned problem can cause premature pump failure by overstressing the pump. Repeated pump failures could be expected.

A new mechanic might help too.

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Good info by TSM.

You stated that the temperature reading is way off from the actual air temperature and the problem occurs shortly afterward. Are you saying that the reading is changing just before the problem occurs or is the reading just way off all the time? If the reading changes then there may be an electrical connection problem causing the trouble.

You may have more than one problem there OP. Having to repeatedly replace a fuel pump makes me think you have some kind of restriction in the fuel flow. That wears out a pump fast. The fuel filter or any other obstruction point from the pump to the fuel rail is the obvious place to start. Do you have a separate fuel filter that can be replaced?

The pump electrical connector can heat up and become intermittent too, even if the pump itself is good. The way to know that this is a fuel pressure problem is to drive the car with a fuel pressure gauge. If the gauge drops to zero and the car stalls you know its a fuel pressure problem.