Hi,

I was hoping you guys would be able to help me with this question. I'm in the later stages of a rebuild and single conversion and will be running a rebuilt auto tranny with a shift kit. I was wondering if I can remove the coolant temperature switch (automatic cars only) on the front of the coolant filler neck. If I ground it, will it fool the tranny computer into thinking the engine is warm at all times? I want to move my aftermarket gauge sender to that spot.

Thanks!

Justin

 

Acording to page K34 in the service manual (wording seems to be mixed up with the ATF thermosensor) the sensor will have continuity above 239 degrees F. So, with that I assume that grounding the wire will fool the computer into thinking that the engine is at normal operating temperature.

 

I wouldnt do that.

Why do you want to 'fool' the trans computer, for the sake of mounting an aftermarket gauge? There are lots of other tappings and blanks on the thermostat casting that the temp gauge sender can be screwed into, without going in the temp switch hole.

If you ground that switch, the trans ECU will think the engine is at fully warm operating temps when it is in fact cold. This means that the trans ECU will run the lower shift points when the car is cold.

The auto trans uses coolant temp to sense the warm up of the engine. If the engine is cold, the trans ECU raises shift points in order to help warm up.

 

Leave the sensor, besides grounding will not simulate normal operating temp it will simulate max temp reading.

 

Also, putting a temp sender in the thermostat housing is a really dumb idea. You have NO reading until the thermostat opens. Read my thread on using a brass T in the TB coolant line.

Dale

 

The car never moves until it is warmed up to normal operating temperature. I still have the factory gauge hooked up as well (for novelty sake). I had the aftermarket sender in a tee on the tb bypass line but I am doing away with it for simplification. I have already tapped and plugged the holes. I am literally getting rid of anything unnecessary under the hood with the exception of A/C, IAC, and cruise control.
This car will never be daily driven, only a toy.
Thanks for the input guys.