Skip the auto shop - Our mechanics make house calls

Q: COOLANT RESERVOIR IS STEAMING HOT

asked by on

What is the problem if my coolant reservoir is steaming hot?

My car has 230000 miles.
My car has a manual transmission.

Hi there. Most of the time when you see "steam" coming from the overflow tank, it’s due to higher than normal or overheating problems within the coolant system. As you know, when coolant and water reach "boiling temperature", water evaporates into steam. The coolant overflow tank has open space, where hot "vapor" has a chance to turn to steam. If your car is overheating, this is something that should be inspected by a local mechanic. If the temperature is good, it typically does not indicate a problem. However, remember this; as coolant and water evaporates into steam, it reduces the amount of coolant inside the motor; so make sure to keep the reservoir full to the indicator line when the car is cold.

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: What is the easiest way to get my charging system tested?

Charging system output, and the integrity of connections in the charging circuit, can be verified against factory specifications if you request an alternator inspection. If you request that service, the responding certified mechanic from YourMechanic will check that for you,...

Q: A whining noise starting at 20 m/ph as well as oscillating noise which speeds up and slows down - coming from drivers side.

Hello, thank you for writing in. Due to having the tires replaced recently, you may have a balance issue. Tires are "balanced" in a process where they spin the wheel on a machine and make sure they turn evenly. Any...

Q: Noise and burning smell from brakes

Hello. Brakes are one of the more important systems on the car, so they should be repaired sooner than later. Being that there are a few variables here I would say there are two options: 1) Take the vehicle back...

Related articles

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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.