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Fuel Pump Relay Issue

  • Thread starter Thread starter Delray Dude
  • Start date Start date Jul 27, 2010
D

Delray Dude

New Member
Jul 7, 2010
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Jul 27, 2010
#1
  • Jul 27, 2010
  • #1
Anyone else ever experience this:

1993 LX 2.3 Notch with the 5-Speed. Started having fuel issues. Symptoms are as follows:

Starting 1st thing in the morning - can hear the fuel pump energize will run for an extended period of time (anywhere from 20 seconds to a full minute) then shuts off. Car will fire and run fine. Trying to start the car anytime before the pump shuts off will result in no start. After the initial wait, if I shut the motor off any time and turn the key to on position, the pump will energize in and shut off in the norm 2-5 second range and engine will fire with no problems.

This also happens at lunch time - (5 hour cool down time) and after work.

Things done to solve problem:
1st - new fuel filter- it definitely need it.
2nd - new pressure regulator - (installed 17 lb injecters while I was there)
3rd - new pump (did last night).

still does it. I suspect the fuel pump relay is the problem, but my question is would it prevent the computer from starting the car until it cycles the relay the 1st time? With the new pump I'm fairly confident the pressure is sufficient to fire the motor after 4-5 seconds but the thing won't fire until I hear the initial pump cut off.

I guess my next step is to locate the "black box". I wonder if any 90 to 93 box will work.

Anyone else experience this problem?
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jul 27, 2010
#2
  • Jul 27, 2010
  • #2
Delray Dude said:
Anyone else ever experience this:

1993 LX 2.3 Notch with the 5-Speed. Started having fuel issues. Symptoms are as follows:

Starting 1st thing in the morning - can hear the fuel pump energize will run for an extended period of time (anywhere from 20 seconds to a full minute) then shuts off. Car will fire and run fine. Trying to start the car anytime before the pump shuts off will result in no start. After the initial wait, if I shut the motor off any time and turn the key to on position, the pump will energize in and shut off in the norm 2-5 second range and engine will fire with no problems.

This also happens at lunch time - (5 hour cool down time) and after work.

Things done to solve problem:
1st - new fuel filter- it definitely need it.
2nd - new pressure regulator - (installed 17 lb injecters while I was there)
3rd - new pump (did last night).

still does it. I suspect the fuel pump relay is the problem, but my question is would it prevent the computer from starting the car until it cycles the relay the 1st time? With the new pump I'm fairly confident the pressure is sufficient to fire the motor after 4-5 seconds but the thing won't fire until I hear the initial pump cut off.

I guess my next step is to locate the "black box". I wonder if any 90 to 93 box will work.

Anyone else experience this problem?
Click to expand...

Something you might to investigate, if simply replacing the fuel pump relay, does not clear the problem.
I had an issue, wherein, fuel pump relay was continually energized changed after turning off the key. Look for a "timer" ckt .
This resulted in numerous low batteries.
 
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