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2004 v6 installed in a 2000 v6 car

Discussion in '1994-2004 V6 Mustang Tech' started by fordmeneac, Sep 17, 2017.

  1. fordmeneac

    fordmeneac New Member

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    hi I have a problem I own a 2000 ford mustang and installed a 3.8 from a 20004 in it everthing works fine ecept the temp sensor and if u go to drive it soon as it shifts gears the mph gauge jumps up to like 120 and cant acelarat let off the gas and it mph drops car runs fine again any sugestions
     
  2. 6 Shooter

    6 Shooter Well-Known Member

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    Did you also switch to a 2004 transmission?
     
  3. fordmeneac

    fordmeneac New Member

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    yes motor and trans both out of 2004 mustang c
    wiring also
     
  4. 6 Shooter

    6 Shooter Well-Known Member

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    You got to either switch transmissions back to the 2000 transmission, OR if keeping the 2004 transmission, get into the current tune (with some help) and change the System Switches>Scalars>Number of Holes for OSS Sensor from 6 to 12. You might call a local transmission shop and find out if it is possible to do the switch mechanically, but would likely cause you to have the transmission torn down to do the switch.
     
  5. fordmeneac

    fordmeneac New Member

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    can I change out the pcm would that help it
     
  6. 6 Shooter

    6 Shooter Well-Known Member

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    Nope. The 2004 PCM requires a CHT sensor and must be wired into the 104-pin harness. Have done that already and it requires some special pins that go into that harness connector which must be drilled out.
     
  7. fordmeneac

    fordmeneac New Member

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    can I change the complete wiring harness from the 2004 w the ecm
     
  8. 6 Shooter

    6 Shooter Well-Known Member

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    Yes, but really difficult as the 104 pin harness passes through the firewall on the far right (from inside the car) passenger side. On the firewall side there is a second harness that hooks up the engine sensors, injectors, coils, O2s, transmission, and maybe some other things as well like the CCRM.