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Can a fuel pump relay go bad if it gets wet?

  • Thread starter Thread starter mob
  • Start date Start date Mar 13, 2009

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
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Dallas, TX
Mar 13, 2009
#1
  • Mar 13, 2009
  • #1
So I moved some of my wires behind my fender yesterday, and today i washed my car. While I was washing it, I started hearing this weird weird noise. I stopped washing it and realized it was my fuel pump started running. I had heard that when the fuel pump doesn't turn off it's probably the fp relay or computer. The car turns on and runs but the fp doesn't turn off unless I take off the battery terminal. I inspected the relay and it was dripping water, was was dripping out from the inside. I figure that's probably it, I called my work and had them order me a new one. Should I change it? Or will it be fine when it drys out? Oh and what wires are the fp relay? I think its the a/c relay that's right next to it, which is which? I am going to have to find a way to water proof these. I am about to put an air filter in my fender, does it get real wet up there when it rains? It looks like that area got soaked with a hose, I cant imagine what tires shooting water up there will do.
 

jrichker

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#2
  • Mar 13, 2009
  • #2
The relay may not be sealed well. Some are and some aren't. Some silicone gasket sealer spread over the seam that goes arond the relay case may help keep the water out of it. Some dielectric grease on the contacts may help prevent them from corroding. Some type of cover over the relay and wires may be needed to keep things dry. Orlando is a very wet place in the summer...
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
2,566
136
104
Dallas, TX
Mar 13, 2009
#3
  • Mar 13, 2009
  • #3
Thanks for that info Joe, I'll use the die-electric grease and a bit of silicone, which relay is which?
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
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#4
  • Mar 13, 2009
  • #4
The fuel pump relay will have a pink/black wire, red wire, green/yellow wire, and blue/orange wire.


diagram of the wiring for 91-93 cars.

Diagram courtesy of Tmoss & Stang&2birds


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Mustang FAQ - Engine Information Everyone should bookmark this site.


Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for94-95 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif
 
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