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91 Ford Crown Vic, no start condition, fuel pump stays running.

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    #16
    What gadget said. If it cranks for an excessive amount of time (>3 seconds) before firing up then you could look into the fuel pressure regulator. That lives on the passenger side of engine under the upper intake on the fuel rail. We had an '89 Town Car which would sometimes fire right up and mostly need 3 seconds or longer to fire. Turned out it the fuel regulator was bad.

    Also, you never answered my question about the TFI module or PIP sensor.
    1985 LTD Crown Victoria - SOLD
    1988 Town Car Signature - Current Party Barge

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      #17
      All of these will bleed down pressure after a while though. Even with everything new, 24 hours later its probably not holding any pressure in the line. I know mine never has. Doesn't stop it from starting fairly quickly even when its been sitting a good while. If it takes a long time to build pressure, thats either a weak pump or a clogged filter most of the time. If it starts hard even with normal fuel pressure, that points at a different problem. Lots of things can make it do that, but watching a fuel pressure gauge while its doing whatever it does will tell you if its a supply problem or not. If it comes up to more than 30psi during the prime period, you're probably fine there.

      still need to get into the engine and be lit off but if you've got solid pressure at the rail you're half good.
      86 Lincoln Town Car (Galactica).
      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

      91 Lincoln Mark VII LSC grandpa spec white and cranberry

      1984 Lincoln Continental TurboDiesel - rolls coal

      Originally posted by phayzer5
      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

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        #18
        My bad for not replying. Yes I did replace the TFI module.

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          #19
          What about the PIP sensor? Those seem to be the real failure point.

          Ashley's old '89 did have good pressure at the rail, something like 33 or 36psi, I can't remember which as that was something like four years ago now and we were trying to figure something else out at that time. It still started hard, had a new fuel filter. Pump's status was unknown. We drove it like that until we sold it, but sometimes (like 1/13 times) it started like my '88- immediately. The other times, it cranked for over three seconds. When we sold it to LTDMan83, he said he replaced the FPR and all was well after that with starting.
          1985 LTD Crown Victoria - SOLD
          1988 Town Car Signature - Current Party Barge

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            #20
            The PIP was replaced too. I replaced that a few years ago. I have spark going to all of the cylinders.

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              #21
              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.

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                #22
                Put in the other pcm and still have the same problem with the fuel pump staying on. I'm thinking it's a fuel related issue where the fuel pump is losing its prime when the car sits overnight.
                It's a possible a line is cracked in the tank causing the a much longer prime.

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                  #23
                  Originally posted by GMP318 View Post
                  Put in the other pcm and still have the same problem with the fuel pump staying on. I'm thinking it's a fuel related issue where the fuel pump is losing its prime when the car sits overnight.
                  It's a possible a line is cracked in the tank causing the a much longer prime.
                  Eh, yes and no. It is possible that the line in the tank is cracked however the car does not know that. The pump prime is always the same length of time, even if there's no gas to pump at all.

                  You turn the key to run. The ECM relay gets power. The ECM gets power, from that relay.
                  Now, the computer turns on the fuel pump relay. The computer knows it only does this for about 2 seconds. The fuel pump relay gets power, and the pump runs.
                  The computer turns off the fuel pump relay, and the fuel pump stops. The computer next toggles on the fuel pump relay when it sees that the engine is rotating (re: PIP signal).

                  If the pump relay is failing, it might be a sign that the pump itself is having a bad time. Especially if any of the wiring to the fuel pump relay looks kind of melty. But, even if the pump was running 24/7 (and you had a magic battery that wouldn't die), the car would start, because the fuel pressure would always be ideal.

                  Did that ECM ground ever get checked out? I'm wondering if a grounding issue is making the computer (both of them, now) angry and it doesn't know what it's doing.

                  Current driver: Ranger
                  Panthers: 83 GM 2dr | 84 TC | 85 CS
                  | 88 TC | 91 GM
                  Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
                  Gone: 97 CV | 83 TC | 04 Focus | 86 GM
                  | Junkyards

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                    #24
                    Hello,

                    Thanks for the input. Where would the ecm ground be located? The pcm does slide into metal slider, so in theory the pcm case should be grounded to that.

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                      #25
                      There are several. One goes direct to the battery, but thats more for sensor grounding reasons. The power ground should be on a green screw located near the hinge. If you follow the bundle coming out of the ECM connector, you'll find it. Its pretty close by near the hinge and the cruise servo.
                      86 Lincoln Town Car (Galactica).
                      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                      91 Lincoln Mark VII LSC grandpa spec white and cranberry

                      1984 Lincoln Continental TurboDiesel - rolls coal

                      Originally posted by phayzer5
                      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

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                        #26
                        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
                        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, starting right up. Have not road tested the car to see how it performs with the pcm that I put in.

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                          #27
                          Continue to keep us updated.
                          ~David~

                          My 1987 Crown Victoria Coupe: The Brown Blob
                          My 2004 Mercedes Benz E320:The Benz

                          Originally posted by ootdega
                          My life is a long series of "nevermind" and "I guess not."

                          Originally posted by DerekTheGreat
                          But, that's just coming from me, this site's biggest pessimist. Best of luck

                          Originally posted by gadget73
                          my car starts and it has AC. Yours doesn't start and it has no AC. Seems obvious to me.




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