I had a similar issue recently and I ended up having two problems:
1.) Air in my coolant line (forgot to bleed the air out properly when refilling coolant previously)
2.) A pinhole leak in one of the hoses, which was causing coolant to weep onto the radiator and evaporate almost instantly. Didn't even smell or anything.
The only way I was able to find the leak (it was in the high side of the line so it only leaked when the car was warmed up and the thermostat had opened) was to drive it until the temperature started to rise and then pull over, pop the hood, and look around at all the lines very carefully before it was able to cool down. I couldn't detect it when just running it in the garage.
Another issue that kept coming up when I was trying to search for solutions on here is that the radiator's plastic end tanks begin to develop hairline cracks and separate from the metal radiator when it gets old and brittle. That wasn't the case for me, but it could be for you. The end result is the same, but it's tougher to detect since the cracks could be out of sight and it is always in direct contact with the metal part of the radiator, meaning the coolant can evaporate instantaneously.
Coolant issues suck. Just make sure to watch that temp gauge until you get it figured out, and always carry some premix with you. Good luck!
1.) Air in my coolant line (forgot to bleed the air out properly when refilling coolant previously)
2.) A pinhole leak in one of the hoses, which was causing coolant to weep onto the radiator and evaporate almost instantly. Didn't even smell or anything.
The only way I was able to find the leak (it was in the high side of the line so it only leaked when the car was warmed up and the thermostat had opened) was to drive it until the temperature started to rise and then pull over, pop the hood, and look around at all the lines very carefully before it was able to cool down. I couldn't detect it when just running it in the garage.
Another issue that kept coming up when I was trying to search for solutions on here is that the radiator's plastic end tanks begin to develop hairline cracks and separate from the metal radiator when it gets old and brittle. That wasn't the case for me, but it could be for you. The end result is the same, but it's tougher to detect since the cracks could be out of sight and it is always in direct contact with the metal part of the radiator, meaning the coolant can evaporate instantaneously.
Coolant issues suck. Just make sure to watch that temp gauge until you get it figured out, and always carry some premix with you. Good luck!
