1991 Ford Crown Vic. No start condition. Fuel pump does not shut off.

[GMP440]

    I have a no start condition on my 91 Ford Crown Vic.
  When I turn ignition key to on position the fuel pump runs but does not shut off.  Before, when the ignition switch is in the on position, the fuel pump would prime for a second or two, go off
  and then the engine would start.
  I checked fuel pressure at the fuel rail, 40 psi.  Have good spark to all spark plugs.  Compression good.  Checked relays too.  All good.
  Also,  Pulled codes with my OTC monitor 2000 and only got a code 81 for the EVP sensor.
  Is this a sign that the ecu or pcm is bad ,not shutting the fuel pump off after the initial prime?  Any help is much appreciated.  Thank you.

[b5blue]

  My 92 Tbird did something similar. If I let it sit with the key in run eventually (2-4 minutes) the pump shut off and the car started if cranked. It would work normal until it sat not used for 2-3 hours. I bought a used PCU on eBay that fixed the problem. (You'll need to match certain model numbers printed on the unit.)  My computer is under the pass. side kick panel. It did not need to be flashed or reprogramed but it will go through a learn mode that will have the car run crappy for a bit.
  Mine cost 30.00, some places sell "tested" or "re-manufactured" for upwards of 200.00. I did clean about 6 large connectors to and near the massive harness around the PCU before buying/installing the replacement. Good luck

[krops cars]

I have a 97 T Bird. Does the same thing as your 91. I agree pcu. Just have not had time to fix right now. If I pull it out side in the winter and try to start it later. It will not. I have to put a battery charger on it, because the fans run also. It takes 5 min. in the winter to shut off or more.

[c00nhunterjoe]

Classic EEC IV pcm failure mode.

[GMP440]

Thanks for the replies everyone.
     Problem fixed.  Did a test someone suggested by turning the ignition switch on to activate the fuel pump.  With pump on, go to the TFI module on the distributer and unplug the ecm connector.  If it goes off then the PIP is getting false signals. Then reconnect to see if the fuel pump does the correct priming. I reconnected the plug back into the TFI module, turned the ignition switch back on.  The fuel pump then did the correct 1 - 2 second prime.  The car then started right up with everything running.  Looks like the ecm plug going to the TFI module may not have been making  good connection with the contact pins on the TFI.  Plug is in tight  and everything is running well.

[GMP440]

Another update:

  The day after the last post I made here; went to start the .  Fuel pump did the continuous running.  Went to the relay box as the fuel pump is running.  Pulled the fuel pump relay.
Then swapped it with another relay.  Put relay in.  Put key on, fuel pump does the correct 1-2 second prime.  Engine running fine.  Road tested the car.  Performs well.
  The only issue now is that when the engine sits over night, the fuel pump takes about 6 seconds to complete it's prime.  Looks like the fuel pump maybe week or it's not holding the prime.
  There is no gasoline smell and don't see any leaks anywhere.

[krops cars]

Do not know where you live. The colder it gets out side the longer the pump will take to shut off. This is what I have learnt about it.

[GMP440]

Hello,

  Here is an update.  Still have the problem with the fuel pump staying on.  Sometimes stays on for 6 seconds, sometimes it's a minute or to with the key in the on position.
  However , when the car starts it runs well on the road.  I have a spare pcm that I have not tried yet.  I'll give an update in the future.

[c00nhunterjoe]

Still sounds like a pcm. You could replace the fuel pump and eec relays as a long shot. But i doubt it.

[krops cars]

I agree.

[Mytur Binsdirti]

A 28 year old Crown Vic....junk it.

[krops cars]

Nice. Some people have to drive betters. If it is in decent shape why not.

[GMP440]

   

   Mytur Binsdirti:  "A 28 year old Crown Vic....junk it."

   I wonder what the purpose of that reply was. 

[Mytur Binsdirti]

Nice. Some people have to drive betters. If it is in decent shape why not.

If one's budget affords one to drive a 28 year old better, then this forum is the last place to hang out and especially ask for Ford advice.

   

   Mytur Binsdirti:  "A 28 year old Crown Vic....junk it."

   I wonder what the purpose of that reply was. 

[GMP440]

  
  I don't really get your responses to this thread;  the car guys discussion is for asking about anything and that includes  about other makes of vehicles.
Some of us that own classic b-body Mopars also own or have owned other vehicle makes and models.  Who cares how old the vehicle is.  Lets make this thread productive.
 I do want to say thanks to those that gave their input on this thread.  

[krops cars]

I spelt beater wrong. Now I will be punished.

[Mytur Binsdirti]

You also spelled spelt wrong.

[krops cars]

Right

[b5blue]

  Hey! Watsamatter? You'd be happy if he drove a modern car with a Fiddler crab face front grill? My 92 Thunderbird is pretty nice and looks good also. Beaters save bucks for restoration and then become Backups. (If worthy.)
  Quit farting around and swap out computers, it won't take long. Check all the connectors in that area for good contact also. 

[krops cars]

Computer through NAPA is around $280.00 programmed.

[b5blue]

I got a "checked out" one off eBay for 28.00. (Returnable for exchange.) They go through a "learn mode" getting better after a few run-stop-run cycles.

[GMP440]

  Update. Tried another pcm and still have the same issue with the fuel pump taking a few minutes to shut off.  I think the fuel pump is losing it's prime even though you hear it running it may
not be picking up the fuel.  Line in the tank may be cracked or broken.  It's just a guess.

[b5blue]

There is a valve on the pump that retains prime. I replaced my pump assembly prior to PCM and it did not fix delayed start issue. 

[GMP440]

  Thanks for the reply.  So, to this day your issue with the fuel pump is still happening?

[b5blue]

  New pump and car started sooner and pump was much more quite. Replaced PCM and checked/cleaned all connectors in the area of the PCM and car fires up instantly after a few start stop run/drive cycles for "Learning". (Has 75K miles in good shape.) Was the replacement PCM tested before install? Mine was.

[GMP440]

  Hello,

  I did not have the pcm tested.  It came out of a running car.  I knew the owner of the crown vic  that the pcm came out of.

[b5blue]

And the PCM numbers match each other? I got a BOSH fuel pump/sender assy. for 26.00 on eBay figuring 92 car, 75K miles it's aged out from sitting around. (200 to install)

[GMP440]

   Update: Yesterday, after I swapped out pcms I reported back that I was still having the same issue with the fuel pump continuously running. Well, later on that day I started the engine. Shut it off, let sit ten minutes. Went back, turned the key to ignition 1, fuel pump ran for a second or two, engine started fine. I let it idle for a few minutes then shut it off. I let the car sit for 30 minutes, came back,went to start the engine, fuel pump ran for a second shut off, engine ran. Later that night tried again. Went to start the engine, fuel pump ran for a second ,started right up.
I let the car sit over night. This morning about 7:30 am went to start the car. Fuel pump on for a second, engine started right up.
Didn't think about it then, but the PCM has to do it's relearning. Once the relearn process is done, then normal operations resume again.
Now the car is starting right up. Have not road tested the car to see how it performs with the pcm that I put in.