Hello Scotty or moderator! I have a 97 Geo prizm 1.6 liter stick shift, and it runs very cold. The temp needle Is always below the bottom line and only in the summer gets close to the middle. Now I'd assume it's a bad coolant temp sensor but my heater on max heat gets only warm at best😥. (Not good for the winter). So does my engine running very cool hurt the car in any way? Sidenote: we also have a 1996 Geo prizm and the heater actually gets hot like its supposed to and the temp needle is always in the middle.
Thanks so much for the help! -Keaton
Thermostats can also stick open - I've had that happen. Engines running cold, especially in the winter, is not good. Combustion of hydrocarbons creates moisture -if the engine doesn't get hot, that moisture can build up in the oil, which can cause poor lubrication, rust of steel parts, etc. Plus, your defroster won't work decently.
Have to checked to make sure there's a thermostat in the cooling system? I have seen them removed completely sometimes.
