What Are the Reasons for Slow Engine Coolant Temperature Rise in Winter?

[GeorgeAnn]

Car winter coolant temperature rises too slowly because of a faulty coolant temperature sensor or a damaged thermostat. After starting, the vehicle undergoes a warm-up process, and slow temperature rise indicates the engine is warming up. The duration of this process depends on the temperature detected by the coolant temperature sensor. The reason for warming up the car in winter is that after prolonged parking, the engine oil flows back to the oil pan at the bottom of the engine. Upon ignition, the upper part of the engine lacks lubrication. After about 30 seconds of operation, the oil pump circulates oil to critical components like pistons, connecting rods, and crankshafts that require lubrication the most.