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Awesome car, but the torque converter is locking and unlocking in OD, throws check engine light. New fluid new filter, didn’t change anything. Is there a way to do a torque converter lock up switch so I can lock it manually in OD? Or should I change the tcc? Would changing the tcm also maybe fix this problem? Thanks
 

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please do not double post, one post is enough. you will need to perform testing on the circuit to see if it is mechanical or electrical failure. yes there is a tcc solenoid but it could be the clutch inside the converter that is slipping as well.
 

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Controlilng the solenoid inside the transmission would let you have contol of the tcc lockup - but unless you only drive on long stretches of open highway, the locking and unlocking with a switch would be a seriously annoying chore. And its very likely that the problem you have is because the solenoid is bad, or not bolted tightly to the top of the valve body, or that the tiny plastic filter going into the tcc lockup solenoid is partly clogged and causing the problem.
The valve body would have to come down out of the transmission - and you would need to wire up a bypass switch (bridging over the control signal to the transmission), and with that much trouble, I personally would figure on rebuilding the F4EAT, (its not very difficult to do; the hard part is getting the trans out of the car and back in again), or take the advice of zzyzzx and disconnect the tcc lockup wire. Do you have the Electrical and Vacuum Troubleshooting Manual (EVTM) for your year of escort? It has all of the wiring diagrams in it.
There are other things that might be responsible for the tcc locking and unlocking. For one thing, the transmission only goes into tcc lockup when in 4th gear, (aka OverDrive), but not if you are using just Drive and the lower gears. There is a switch atop the transmission that is called the Neutral Safety Switch. It has 3 functions, such as preventing starting unless the shift lever has the transmission in Park or Neutral. It also turns on the backup lights when in reverse. Its 3rd function is to let the Transmission Control Module know whether you want to use all 4 gears, or just the lower three. Thus if this switch was dirty and making a bad contact from vibrations, it might be telling the TCM to unlock the tcc clutch from time to time. Also, there is a Turbine Speed Sensor atop the transmission, right next to the iron casting on the end of the transmission. This would only be visible with the battery and battery tray out of the car. The Transmission Control Module uses the input from the Turbine Speed Sensor to decide when it is time to lockup or unlock the clutch inside the torque converter. And the TCM needs to know how fast the car is going, so the Vehicle Speed Sensor needs to be feeding its signal to the cars main computer too.
Some of this stuff is no longer available except "maybe" from a junkyard, and not easy to get to even then.
If your escort is a 92, the Transmission Control Module is a light colored box located more or less straight up from the driver's left foot. You can see if with a mirror held below the dashboard. The TCM exchanges info with the PCM for decisions on upshifting, downshifting, and torque converter lockup.
 

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Can I just put the torque converter on a switch? Witch wires off the tcm do I need to do so?
ya, sure. but there is a reason why your symptom is happening. i would try to solve that problem and allow the system to work how its supposed to. maybe consider taking it to a transmission shop.
 
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