What is this switch / sensor for?

[dimension12]

Was changing auto trans mount and found a 2 wire connector unplugged. Plugged into sensor located at rear of pan on driver’s side. Now I have a surging at highway speed and the shift light flashes with the surge. What s the switch/sensor for. 99 sport 3 speed auto 4.0.

 

[Squatch]

Does the plug look like this? If so, it's for your lock-up torque convertor, as best I can tell. I'm sure there will be someone on here that actually knows the answer, but this is what I came up with when I looked into it.

 

[dimension12]

That’s it. What is the repair for the surging? Replace the solenoid?

 

[Squatch]

Was your rig surging before you plugged the switch in?

 

[dimension12]

Was your rig surging before you plugged the switch in?

Nope. Unplugged it until spring. Will replace the solenoid then.

 

[Squatch]

And with the switch unplugged, it doesn't surge?

 

[dimension12]

And with the switch unplugged, it doesn't surge?

Correct. Surging is from converter locking and unlocking I believe.

 

[Jerry Bransford]

That lockup for the torque converter helps the transmission run cooler, not to mention you'll get better mpg. Both benefits from it stopping the slippage inside the fluid-filled torque converter.

 

[dimension12]

That lockup for the torque converter helps the transmission run cooler, not to mention you'll get better mpg. Both benefits from it stopping the slippage inside the fluid-filled torque converter.

It is extremely cold in Minnesota right now. It’ll have to wait until early spring. Going to replace pan with an extra capacity and drain plug at the same time.