Q: Car Overheating; Unknown cause

asked by on

For the past week or so, my car has been overheating with no visible leaks, no smoke/steam, oil looks clean, everything seems okay. It will overheat, I'll pull over ASAP, turn it off, let it sit for a while, then its back to normal. Could this be caused by a bad water pump? Any specific indicators I should keep an eye out for?

My car has 208053 miles.
My car has an automatic transmission.

The coolant could be low, the thermostat could be plugged up or sticking, the radiator could be plugged up restricting the coolant flow, the water pump could have failed, or the head gasket could have burned causing the engine to overheat. Check the coolant to see if its full. If the coolant is full, then feel the upper and lower radiator hoses and see if they are about the same temperature. If they are, then the radiator and water pump is working. If they are not, then either the water pump has failed or the radiator is plugged. If the engine overheats when at a stop, then it would be a radiator. If the engine overheats at any speed, then it would be a water pump. Now, if the hoses are the same temperature, then the thermostat may be sticking or plugged up. To test this, turn on the heater and see if it blows hot or cold. If its blows cold, then the thermostat is sticking closed or plugged up completely. If there is no signs of a failed thermostat, then the head gasket has burned. Usually you will get a white smoke or a sweet smell at the exhaust system if the head gasket is burned up. If the engine coolant temperature gauge says that the engine is overheating, but the actual temperature is normal, then the temperature gauge or the sending unit is not working properly. If you need further assistance with your vehicle overheating, then seek out a professional, such as one from Your Mechanic, to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Car Overheating; Unknown cause

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Q: Car overheats

Overheating can be caused by something as simple as low coolant level, or something as major as a blown head gasket, or a crack in the cylinder head or block. The cooling system should never be checked if the engine...

Q: Location of coolant temp sensor

The ECT (Engine Coolant Temperature) sensor is mounted directly in front of the exhaust port for cylinder number one, right next to the exhaust manifold. It is mounted on the head, on the left side of the motor on the...

Q: 2013 Toyota Highlander making a lot of noise from waterpump, and I'd like to know to expect in terms of repairs.

The engine has to be removed in order to replace the water pump on this engine. The labor just for the water pump is 13 hours. This does not include diagnosis or additional repairs needed like thermostat or any other...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.