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Discussion Starter · #1 · (Edited)
93 3.8L ran great, now won't start, fan & fuel pump runs constantly with key turned

I just got an amazing deal on a 1993 Ford Taurus LX

Has been garage kept for 3 years

I drove it all day, made multiple stops, parked it at night, woke up and it won't start

First thing I realized is the Fuel Pump & Cooling Fan is running continuously with the ignition turned

Cleaned the CCRM ground connection and still having the same issue

I appreciate any help big time
 

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^^^^ +1

Either a faulty PCM, or possibly PCM ground problem.
 

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^^^ It isnt pressure that turns off the pump with key on, as the PCM does not have any idea what the pressure is anyway. Pump shuts off after a programmed in time delay of about 2 seconds.
 

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^^^ It isnt pressure that turns off the pump with key on, as the PCM does not have any idea what the pressure is anyway. Pump shuts off after a programmed in time delay of about 2 seconds.
If that's the case, it shouldn't be. :rolleyes2: Seriously, who would design a pressurized pump system without a pressure shutoff switch?
 

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Everyone..... Only the returnless fuel systems monitor fuel pressure with a sensor on the rail. Ford started with returnless systems in 2000 on most cars/trucks.
 

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Everyone..... Only the returnless fuel systems monitor fuel pressure with a sensor on the rail. Ford started with returnless systems in 2000 on most cars/trucks.
:werd:

Fuel pump primes the system based on a set time the PCM cycles the pump for. The fuel pressure regulator mechanically regulates the pressure bases on vacuum load. Returnless systems change the speed of the fuel pump by pulse width modulation to control pressure and volume of fuel.

And to add to the issue I have had my PCM fail with the same symptoms fuel pump continuously running, as well as the cooling fans. Another member here had posted to my topic reguarding this and said that this is usually a sign of a failed PCM. I traced my wiring and performed a number of test on the CCRM and all wiring relating to the symptoms I had. After it all checked out I was able to determine I had a PCM that failed.

Both links are to the topics I posted about my PCM. The first one was when it left me stranded. The second is where I posted about it being fixed.

http://www.taurusclub.com/forum/82-maintenance-repair/158090-broke-down-while-driving.html

http://www.taurusclub.com/forum/82-maintenance-repair/158664-pcm-bad.html
 

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Discussion Starter · #11 ·
The CCRM tested good and i tried a replacement and still no luck
I checked and cleaned all ground terminals I can see, will try a new PCM tomorrow

Can I test the PCM to verify failure? Continuity, resistance, etc?
The PCM is the ECU located behind the glove box correct?
 

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No testing that I know of for a PCM test. All you can really do is trace it down to the PCM so long as everything else checks out good. Make sure the numbers on the PCM are the same as what you have in your car. As for location I'm not sure about a '93. I know on 3rd gen's they're in the firewall under the hood.
 

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The computer is located in cabin, passenger side, behind the glove box at the firewall above the A/C recirculation ducting. Remove the battery B- cable, remove the glove box & go at it that way.

I've heard that some autoparts stores can check the computer, so maybe it's worth a call or two???? If you have an obvious component problem, a good electronic tech could probably repair it & if you buy a reman it should be worth a core charge, because they'll try & repair & resell it!!!!
Let us know what you find.
 

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How is your trouble shoot going???

Another thought came to mind, you said that you checked the CCRM grounds, I assume you meant the ground points at the upper radiator support locations, But did you pull the ground wiring connector, sometimes located sorta out of sight behind the upper radiator hose & check it's pins & sockets for damage, or corrosion???? It's a common problem point, causing the type of trouble your reporting.

More thoughts for consideration, let us know how it's going.
 

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Good find, fix, feedback & to hear your "on the road again"!!!!

I'm having similar random stalling problems with my 94 3.8L & also have the fan & fuel pump cycling on, or running when they shouldn't be & the more I read of the engine just randomaly ceasing to run/stall, with the fans & fuel pumps cycling, or running after the stall, or otherwise acting up, like coming on before a cold start up & after the owner has done an IRCM check out, or replacement, grounds checking out, B+ voltage drops checking out, all by members with similiar vintage vehicles, the more I'm coming to the conclusion I too may be having ECM problems & today was scheduled by me to work my Bulls problem some more, so good timely input for me, thanks for posting the conclusion of your trouble shooting results!!!!
 

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CCRM ground

have a 1993 that won't start- no fuel pressure, checked voltage at inertia switch, had 10.2v at switch, checked pump, had 10.2v at pump. Therefore replaced pump b/c figured i had voltage. New pump, still dosent work.(but works when hooked up to battery)WTF???? Started to trace wiring harness, read forum about CCRM, messed with that, found ground connection that went back to CCRM. removed old ground connection plug and jumped it....holly crap it worked!!!!...the moral of the story...10.2v is not 12v...must have 12v to spin that fuel pump...check the ground!!!! (its two little wires that is screwed on the the metal right in front of the battery, then it goes back about a foot then has a gray clip connector, that connector was my problem...FYI..thank you to everyone who took the time to respond to this thread, it helped me, I hope this post will help someone else..
 

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:werd:

Fuel pump primes the system based on a set time the PCM cycles the pump for. The fuel pressure regulator mechanically regulates the pressure bases on vacuum load. Returnless systems change the speed of the fuel pump by pulse width modulation to control pressure and volume of fuel.

And to add to the issue I have had my PCM fail with the same symptoms fuel pump continuously running, as well as the cooling fans. Another member here had posted to my topic reguarding this and said that this is usually a sign of a failed PCM. I traced my wiring and performed a number of test on the CCRM and all wiring relating to the symptoms I had. After it all checked out I was able to determine I had a PCM that failed.

Both links are to the topics I posted about my PCM. The first one was when it left me stranded. The second is where I posted about it being fixed.

Broke Down While Driving.

PCM Bad???
 

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I appear to be having a similar problem as discussed in this thread with constant running fuel pump and a car that doesn't start. I have a 1994 Taurus. I have tried two used CCRM. My question is the CCRM and the PCM two different modules? Where is the PCM located?
I have the car at the mechanic right now and they think the tank needs to be dropped and the fuel pump replaced. I don't think the fuel pump is the problem.

Thanks in advance!
 
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