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Fuel pump stays on when car is off...please advise.

  • Thread starter Thread starter PrimerdFury
  • Start date Start date May 29, 2004

PrimerdFury

New Member
Feb 26, 2003
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Fountain Hills, Arizona
May 29, 2004
#1
  • May 29, 2004
  • #1
My car runs perfect..however, when I turn the car off and take the keys out of the ignition I can still hear the fuel pump on. Could it be the fuel pump relay and if it is where is it on a 1986 LX? Everyone says it is under the driver's seat but I don't see it...is it under the carpet? Thanks.
 

ECU5.0

Banned
Jan 10, 2004
1,803
1
0
raleigh, nc
May 29, 2004
#2
  • May 29, 2004
  • #2
had the same thing happen to me not two weeks ago. its hard to see...but it was right behind that little hump near the front of the seat. slide the seat all the way back and stick your hand under there. you should be able to feel and metal bracket and its connected to that. it was actually easier to once i took the seat out. its like 8 bucks or something at autozone
 
T

TheUser

Active Member
Jul 25, 2003
1,859
1
36
Springfield, MO
May 29, 2004
#3
  • May 29, 2004
  • #3
I'm not sure where it's at on an 86, but 87-92 is under the drivers seat above the carpet. It sounds like it's your fuel pump relay indeed, once you find your relay, wait until it does that again and tap the relay and if the fuel pump shuts off, you know it's the relay, or just replace it lol. There's a fuel pump connection behind your rear bumper cover, it's a pull-apart connection that connects the fuel pump harness to the wiring from the inertia switch...you can pull it apart and shut the pump off if you don't want it on when you're parked...I did that for about 6 months and mine just stopped staying on...weird.
 
8

87'GTstang

New Member
Feb 16, 2004
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May 29, 2004
#4
  • May 29, 2004
  • #4
Here's the technical explanation. A relay is a simple switch, any time a signal energizes the circuit it energizes a magent which completes the circuit and power flow to the intended device. These things wear out and in this case, the relay for the fuel pump that is, the contact that swings to the magnet has frozen in place from age, so it cannot cut off. Go to your parts store and say you need a fuel pump relay which looks like a 1"x1"x2" gray box. It's about $15. I suspect the same thing happened on my car sometime ago which is why some idiot along the way decided to hotwire the fuel pump from the battery which also bypassed the saftey inertia switch
Anyway, when all was hooked back up "correctly", the same scenario was wrong with mine.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 29, 2004
#5
  • May 29, 2004
  • #5
if not mentioned: if the FP relay does not cure it, the same thing can happen from a bad EEC relay (same idea, but upstream - FP relay gets input from the EEC relay output).
good luck.
 

PrimerdFury

New Member
Feb 26, 2003
139
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0
Fountain Hills, Arizona
May 29, 2004
#6
  • May 29, 2004
  • #6
HISSIN50 said:
if not mentioned: if the FP relay does not cure it, the same thing can happen from a bad EEC relay (same idea, but upstream - FP relay gets input from the EEC relay output).
good luck.
Click to expand...

where would I find the EEC relay and is it also like 15 bucks?...I'm about to head down to autozone to buy the fuel pump relay so I might as well get both.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 30, 2004
#7
  • May 30, 2004
  • #7
i did not mention it earlier cuz i dont know where it is on a 4 eye. on 87 and up, it is above the puter (pass kick). i like your thinking - check the FP relay first. go from there. the EEC relay energizes a bunch of other things, so i think you might know if it was at fault.

good luck. BTW, i dont know about availability or price. good luck.
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
May 31, 2004
#8
  • May 31, 2004
  • #8
The EEC relay and the fuel pump relay are the exact same relays. Last time I checked they were like $12 at Autozone, but I always pick up a few spare ones at the Pick a Part yard.
 
8

87'GTstang

New Member
Feb 16, 2004
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Jun 1, 2004
#9
  • Jun 1, 2004
  • #9
trbkrb said:
The EEC relay and the fuel pump relay are the exact same relays. Last time I checked they were like $12 at Autozone, but I always pick up a few spare ones at the Pick a Part yard.
Click to expand...
I hear ya, I seem to be loaded up with all kinds of fuses and relays these days
 
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