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Fuel pump relay getting hot?

  • Thread starter Thread starter Peg8687
  • Start date Start date Nov 10, 2007
P

Peg8687

New Member
Feb 9, 2003
346
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Orignally NC, Currently Valdosta Ga
Nov 10, 2007
#1
  • Nov 10, 2007
  • #1
Started off one day i ran my car out of gas idleing in the driveway. Fuel pump started sounding a little sick while priming after that. One day i go out to start it up and no pump prime. Go through the basics, inertia Switch good, replace relay, yadda yadda nothing. Jump the pin on the EEC test point to ground and no pump prime still. Bought a new 255lph pump but waiting to install it. Saturday rolls around and the batt is dead in the stang for sitting for a while. Charge it up, throw in back in the car and WHAM! stock pump primes and car starts...let it sit and idle while i tinker around under the hood and it dies again. Just like it died of Natural causes, idle lowered down a little at a time and then just cut off. But now the Pump isnt priming again. But as soon as it died i went to the relay under the seat and the relay and the wiring running to it were pretty warm.


WTF?! should i still replace the pump then keep shooting from there?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,797
3,930
183
Claremore, OK
Nov 10, 2007
#2
  • Nov 10, 2007
  • #2
I would suspect the motor on the fuel pump to be a goner. The charged battery had a high enough voltage and deep enough charge to get the old motor running again but as the motor heated up and the tolerances decreased it most likely locked up again. You already have the new pump so just replace it.

Darren
 
P

Peg8687

New Member
Feb 9, 2003
346
0
0
Orignally NC, Currently Valdosta Ga
Nov 11, 2007
#3
  • Nov 11, 2007
  • #3
Any Idea why the relay was getting hot though?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,797
3,930
183
Claremore, OK
Nov 11, 2007
#4
  • Nov 11, 2007
  • #4
As the fuel pump gets hot and quits working the voltage is going to drop and the amperage is going to increase. Think of a dead short and how the wire gets so hot it smokes.. The increase in amperage is going to overheat the realy as it is most likey only meant to handle 20 or 30 amps. Unplug the fuel pump back at the rear of the car and see if the relay continues to heat up. There is a connector just between the rear bumper and the fuel tank and you do not have to remove the tank to get to it.

Darren
 

corvetteguy

New Member
Jun 30, 2007
71
0
0
Nov 12, 2007
#5
  • Nov 12, 2007
  • #5
The fuel pump rely's on the flow of cool gas
to keep the tiny motor from seizing up.
If you let the tank run dry, DON'T CRANK AND CRANK
you will only seize the $100 motor.

The increased current probably overheated the relay
contacts so it will now be intermittent $12 will fix the
relay.
 
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