Transmission not shifting smoothly when warm

2001 FORD WINDSTAR
185,000 MILES • V6 • 2WD • AUTOMATIC
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CLAUDIA POW
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Most of the time the transmission is fine, if I do a lot of driving where the engine and transmission gets hot (not overheating) just regular running hot. The transmission does not always shift smoothly into the next gear. If I take my foot off the gas for a second it will go into gear. Fluid level is good and not dark. Is there a sensor that is not working properly.
Aug 12, 2018 at 2:45 PM
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ASEMASTER6371
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Good afternoon.

Yes, the throttle position sensor is what controls the shift points along with the valve body.

You should check the voltage at the sensor. You should have a 5 volt feed, a ground, and a signal wire. the signal wire should be about .5 to .75 volts at idle. Then when pushing down the pedal, it should go up to around 4.8 volts.

Do that check with the engine off key on.

I would also change the oil/filter in the transmission in case the filter has a partial restriction.

Roy

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission
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Aug 12, 2018 at 3:28 PM