Temperature gage started to show signs of overheating?

BOILER782003

MEMBER
1998 MAZDA 626

I was driving down the freeway when my temperature gage started to show signs of overheating, I turned on my heater and continued, it passed the over heating mark and started to loose power, by the time I pulled over and shut off the car, white smoke was billowing out the hood. My radiator cap was loose, I added antifreeze 50/50 water. Now it wont start, everything turns over and has power what should be my first steps?

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

This no start could be due to coolant temperature sensor malfunctioning.
The overheating could have malfunctioned the sensor. When a temperature sensor malfunctions, it sends incorrect data to the ECM, it could send a signal that the engine is 'too hot' and the ECM will not let the engine to start.

https://www.2carpros.com/articles/how-a-coolant-temperature-sensor-works
https://www.2carpros.com/articles/symptoms-of-a-bad-coolant-temperature-sensor
https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

The coolant temperature sensor is located on the top of the engine (see diagram below).
Check the resistance value of the temperature sensor. I included the testing procedure and the resistance value below.

Please let me know of any questions.
Thank you.

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