Are the inline coolant adapters that are spliced into the upper radiator hose accurate? Or does it seem like a poor place to place the sensor since it is so close to the end tank?

 

Yeah, I wouldn't want one. Tuning warmup would be a pain, I don't see how it could read anything but cold, cold, cold, now at temperature.

I think the same would be true for pretty much any sensor on the other side of the thermostat, pretty much useless till at temperature, but probably pretty accurate from there.

I've got mine tee'd into the heater core circuit, and it seems to work really well for a street car. I'm not sure how accurate it would be if the thermostat is fully open for any length of time though.

 

I've read about more than a couple folks having problems with them depending on how the sensor is setup. A lot of sensors are single wire resistive units that don't ground real well through a rubber hose You need to run a wire from the block to the adapter. Same thing with thermoswitches for fans. What is the application here?

 

My truck's stock coolant temp gauge broke. It probably was a dummy gauge to begin with.

I'd like something simple and accurate to monitor coolant temp.

 

Does the ECU also use that sensor? If not, it might be worth pulling it out and sticking the aftermarket sender in that location. Plenty of thread adapters exist for just this reason, its totally worth the $5-$10 just so you don't have to retap the block or something equally silly. There may also be other plugs you can sub for a sensor as well.

What kind of truck?

 

It's a 93 Toyota T100. I wasn't sure if the sensor or gauge is bad. I guess I should check that first