Hi, How do I tell that my car is overheating? The previous owner suspected that the gauge is faulty. When it is all the way up, even on the orange/red area, the car is still running just fine. Both upper and lower radiator hoses are very firm and plumpy, are they normal when the engine is running after 15-20 minutes? thersmostat is new, waterpump is said to be 4yrs old. i drained and redrained the radiator 3 times, but the gauge still very high or on red area. asm