Skip the auto shop - Our mechanics make house calls

Q: Car Overheating

asked by on

I just topped off my coolant, but my car temp is still getting very high and close to over heating within two miles of starting to drive. There is no noise from the water pump. Is is possible that I just need to replace the thermostat?

If your coolant level was really low and you added coolant you could have air trapped in the system that creates a block to normal circulation. There are little weep holes set high in the coolant "piping" that allow you to purge air as you add coolant. Normally, these are opened when you are refilling a totally empty system in order to avoid trapping air and creating a blockage.

A malfunctioning thermostat is a common cause of overheating but before you condemn the thermostat make sure radiator electric fan(s) are fully functional, radiator is not obstructed with external debris, radiator is not internally plugged with sludge, and you don’t have a collapsed rubber coolant hose. There are some checks a mechanic can do to try to assess flow rate to see if thermostat is not open and/or radiator is plugged.

Note that if car is seriously overheating, you can easily cause significant damage to the engine via warping of the head and/or block. If it’s overheating at all, the prudent thing is to not drive the car until it is repaired; that will help you avoid needless additional problems. YourMechanic can evaluate the overheating situation for you and will be pleased to do so.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: Vehicle overheating

Hello. There are several different parts of your cooling system that could cause your car to overheat. A bad water pump, radiator, faulty thermostat, clogged heater core, or leaking or clasping cooling hoses could cause this issue. The worst case...

Q: Antifreeze coming out

Hi there. It is possible you may need to replace your thermostat. The thermostat opens when the car gets warm to allow more coolant to flow through the cooling system. When it fails, it can become stuck closed and will...

Q: Issues with coolant pouring out of the overflow

Hi there. If the engine is losing coolant, then the location of the leak needs to be found first. A leak will allow the coolant to get low enough to cause it to overheat. I start by doing a pressure...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...