Lately I've noticed my car does NOT heat up above a quarter on the temperature gauge next to the speedometer. I was just wondering if this means I have a problem with the thermostat/radiator? What could be causing this? Is it normal?

 

If you have difficulty reaching operating temp, it's most likely the thermostat. It's more than likely stuck fully open and can't restrict flow / temperature. To be absolutely sure about what's going on, I'd suggest sticking a coolant thermometer into the radiator filler neck and check it (the coolant temp) manually. These look like cooking thermometers on steroids.

P

 

Same thing happened to me on my Civic. Tried 3 thermostats, and the problem still persisted. Turns out it was a bad gauge or coolant temp sensor.