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Discussion Starter #1
I own a 93 lx 2.3 imp getting 6 volts to the fuel pump and cant figure it out im about to trace the wires back from the pcm any thoughts where my prob might lie?

 

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redneck_ferrari said:
I own a 93 lx 2.3 imp getting 6 volts to the fuel pump and cant figure it out im about to trace the wires back from the pcm any thoughts where my prob might lie?

Try Replacing the FP Relay (under the Drivers Side Seat...) it may be dirty contacts in the relay
 

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Discussion Starter #3
that might be it for a v8 but the 2.3 four cyl. has no fuel relay
 

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redneck_ferrari said:
that might be it for a v8 but the 2.3 four cyl. has no fuel relay

Hmmm.... you workin on a carbed model then???

1987-93 all EFI Mustangs had a fuel pump relay, as well as a fuel pump cut off switch in the back.

Unless your 1993 LX has a Carb and a Manual FP it has a Fuel Pump Relay under the Drivers Seat.
 

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Discussion Starter #5
It is an EFI the four cyl's have no relay that I know of I looked at the wiring diagrams in the Hanes manual and straight shot from the pcm. to the inertia switch at the back of the car. it does however tie in to the constant control relay module.
 

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The relay is built into the constant control relay module. You should have 12v out to the inertia switch.
 

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Okay... I may have been wrong on the relays location... but I was right on the fact that a Relay exists. The ECM sends a ground signal to the relay... and the relay feeds power after the ground signal is triggered.

if the contacts in the relay are dirty then the power cant get through to the Fuel Pump... therefore and thus... check the contacts at the relay control panel. and then check and / or replace the Relay.
 

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everyones on crack

you all have a part of it right xr4ti,there is a relay under the hood in the constant control relay centre if you open it it has 3 relays in it , so to end all arguments find the eec test connect a test light to power and stick the other end in the test harness on the wire coloured light blue and orange, turn the key forward, if it lights up you have the proper ground signal to your fuel pump relay. the ecm cannot put out enough amperage to power the f/p. so to keep the ecm from getting hot, they send ground signals to relays, it's alot easier. the dis system had to be the reason they moved the f/p relay, i liked it under the seat. CHANGE THE RELAY SO YOU CAN DRIVE THE DAMN CAR! LOL ! were only trying to help man.
 

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Discussion Starter #9
thanks for the help i will have to try when i get back home.
 

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I am having the same problem--only getting 6.x volts to the pump. Checked the lines from the harness under the fuse panel to the pump and they're okay. Messed around for a few hours, checking wires and after a while it just started working again. Couldn't find a problem if there wasn't one so I just started driving again. Well, it's back again and I need to fix it. From what I've read hear and other posts, sounds like it's the Constant Control Relay Module (CCRM).

So, the CCRM is the black box with a large amount of wires coming in on the passenger side of the car, correct? Should I assume that it's the problem? Any way to test?

Also, what does this tell me about the problem?

so to end all arguments find the eec test connect a test light to power and stick the other end in the test harness on the wire coloured light blue and orange, turn the key forward, if it lights up you have the proper ground signal to your fuel pump relay.
I read in Chilton's to do something similar and if the pump runs... or doesn't run... then what? When I did it nothing happened, what does that mean? Did not try the test light, however.
 

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fuel pump

i'm not familiar with a big black box, is it efi? it should be a green relay under the driver seat, test there fo voltage, but be sure not to short out the eec wire it's a neg signal.
 

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who says you need a fking-relay,i have wired the fuel pump direct to the battery using a 110 house switch( they never burn out/melt) place it under the seat ,just click the switch on and start the car,an indicator light on the dash might be helpful so you won't forget to shut it off in case your deaf and can't hear it running,, having control of the fuel pump is also helpful in case your flooding the engine in a no start condition,like weak plugs or in extreme cold weather when flooding is common on those who don't do tuneups ,good anti-theft gadget also,,
 

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who says you need a fking-relay,i have wired the fuel pump direct to the battery using a 110 house switch( they never burn out/melt) place it under the seat ,just click the switch on and start the car,an indicator light on the dash might be helpful so you won't forget to shut it off in case your deaf and can't hear it running,, having control of the fuel pump is also helpful in case your flooding the engine in a no start condition,like weak plugs or in extreme cold weather when flooding is common on those who don't do tuneups ,good anti-theft gadget also,,
That is my last resort.
 

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relay

i had to use a switch cause my ecm quit sendint a signal but i still used a relay, i feel safer that way.
 

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Okay, so let's say that I don't want to use a switch to run my fuel pump, because I don't. Anyone have any suggestions on how to check the Constant Control Relay Module on a 1993 2.3L? I don't want to start playing the part replacing game... that gets expensive. Can the CCRM be opened and inspected? Any help would be great, I am pretty much lost on this one.
 

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need so me help too

i need to know what color the power wire is coming off of the fuel pump on a 92 lx 2.3 i know i could use a test light but i have no power going to the fuel pump and i would like to run a hot wire for it.
 

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i need to know what color the power wire is coming off of the fuel pump on a 92 lx 2.3 i know i could use a test light but i have no power going to the fuel pump and i would like to run a hot wire for it.
It's Black with a Pink stripe right at the pump up until the Inertia Switch. After that it is Dark Green with a Yellow stripe.
 

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thank you now i guess i will run a hot wire for the pump
You have no power at the pump? I had 6.x volts back at the pump. It turned out to be the Constant Control Relay Module (CCRM). I tested the line all the way from the CCRM to the pump and it was okay. Also tested the feed from battery to the relay and it was okay.

When I ran the Key On Engine Off Test I got code 543 which is Fuel Pump Secondary Circuit Failure: Batt to ECA. You might try doing that test. I forgot to right away because there is no check engine light to remind me.
 
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