2002 Ford Explorer Fuel Pump fails in hot weather when car

Tiny
GNOCHTA
  • MEMBER
  • 2002 FORD EXPLORER
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 76,000 MILES
My wife's 2002 explorer has a very weird problem. If the temperature is above 85 degrees, she'll get in her vehicle and drive it home. When she shuts off the engine, it will not start again. If I lay under the car, and have her turn the key to the on position while the car will not start, I can not hear the fuel pump come on to pressurize the fuel system. Once the evening comes and the temperature cools, the vehicle starts right up as if nothing is wrong with it.
If the temperature never reaches the mid to high 80's, the vehicle will not fail. I changed the fuel pump relay and that was not the problem. Could this actually be a bad fuel pump even though it works fine when the weather stays cool or if the vehicle is not shut off when it's hot outside?
Do you
have the same problem?
Yes
No
Wednesday, July 14th, 2010 AT 1:23 AM

6 Replies

Tiny
JACOBANDNICKOLAS
  • EXPERT
The only thing I can suggest is to check to see if there is power to the pump or relay when it gets that hot to see where the break down is. If you don't hear it run, either there is a broken wire or the pump is bad. When this happens, check to make sure there is power to the relay and let me know what you find.
Joe
Was this
answer
helpful?
Yes
No
Friday, July 16th, 2010 AT 12:15 AM
Tiny
GNOCHTA
  • MEMBER
When the vehicle fails, if I put a volt meter on the plug that connects to the intertial safty switch I see a 12 volt pulse that comes from the fuel pump relay when the ignition key is turned to the on position. If this 12 volt pulse goes directly to the fuel pump to pressurize the fuel system prior to engine start, then yes the 12 volts is getting there. I can also put my hand on the fuel pump relay and feel it actuating.
I jumpered across the plug to the inertial safety switch and eliminated the inertial saftey switch. I also switched out the fuel pump relay just to make sure and eliminate it too. The odd part of all this is that the fuel pump seems to work fine as long as the weather is not hot. If the outside temperature stays below 85 degrees, the vehicle will not fail. Very strange to say the least.
Was this
answer
helpful?
Yes
No
Friday, July 16th, 2010 AT 7:49 AM
Tiny
JACOBANDNICKOLAS
  • EXPERT
This is an interesting one. If you are getting power to the pump when it is hot, it has to be bad and not working when it gets too hot. That is the only thing that makes sense to me.
Was this
answer
helpful?
Yes
No
Saturday, July 17th, 2010 AT 12:27 AM
Tiny
GNOCHTA
  • MEMBER
Yeah we have the vehicle in the shop right now getting the fuel pump and filter changed. I will update you on the results. Talk to you soon George
Santee, CA
Was this
answer
helpful?
Yes
No
Saturday, July 17th, 2010 AT 12:17 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Let me know. This is one for the record book.
Was this
answer
helpful?
Yes
No
Sunday, July 18th, 2010 AT 1:10 AM
Tiny
AMO1976
  • MEMBER
Did you ever get this resolved? My husbands truck is doing the same thing and is in the shop right now. They replaced the relay and just replaced the pump but took the car for a ride and shut it off and now it's doing the same thing. We thought that the heat had something to do with it but it's doing this now in the cold weather too? Any advice would be most helpful!
Was this
answer
helpful?
Yes
No
Tuesday, February 22nd, 2011 AT 8:41 PM

Please login or register to post a reply.

Recommended Guides