1995 f150 erratic downshift

Discussion in 'Engine & Performance' started by Deviljohn, Jul 5, 2017.

  1. Deviljohn

    Deviljohn Junior Member

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    1995 Eddie Bauer
    5.0L 302 V8
    trans 4R70W 3.55 non ls
    170k mile, tranny has been rebuilt (prior owner)

    Getting error code 632 during KOER self test, and yes cycling the od button on and off with engine running....(the od on/off light functions so assume the switch is good..)

    symptoms are erratic downshifting/upshifting driving 40-50 mph (feels like truck shifting down to 3rd and back to 4th...rpms jump from say 1500 to 3000..

    have researched here and there, suspecting throttle position sensor? and/or torque converter solenoid? Any help on where to begin?
     
  2. Roush PSD Interceptor

    Roush PSD Interceptor Straight Piped Diesel Staff Member

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    Process of elimination.

    Does the engine stumble or
    run uneven in park when running
    it at the same speed you are
    having the transmission
    up, down shift trouble ?
    Looking for the bad point on the TPS reostat. (Variable
    Resistor).

    If not I would say the TPS is
    not the problem. It is the cheaper part, about $32
    depending on where you buy
    it.

    Now since it is a shifting
    issue, more than likely it's
    the shifting solenoid.

    Just your luck it's the most
    expensive part I saw, but
    there are different solenoids
    in that 4R70W.

    Hope this helps.



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    Last edited: Jul 6, 2017
  3. Roush PSD Interceptor

    Roush PSD Interceptor Straight Piped Diesel Staff Member

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    Have any luck yet in diagnostic @Deviljohn ?

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