Skip the auto shop - Our mechanics make house calls

Q: Reservoir coolant boiling.

asked by on

Sometimes the coolant in the reservoir starts to boil.I check the hoses and they aren't hot or stiff from too much pressure. Also, the temperature falls within good operating temperatures.

Hello! The cooling system removes a lot of heat from the engine and this process can create a lot of pressure. Expansion tanks or coolant reservoirs are designed into many of these systems. These tanks are used to bleed off extra pressure beyond the systems maximum safe limits and the fluid is able to escape into these tanks. Have a mechanic, like the ones at YourMechanic, inspect the cooling system to ensure proper cooling system fluid level and operation.

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: P1684

P1684 indicates that the engine control unit / powertrain control module memory was cleared at some point within the last 50 ignition cycles - start/drive/turn off. If the battery was replaced or disconnected, it can leave this fault code in...

Q: The car is burning oil significantly

Hello. Thanks for writing in about your 2004 BMW 330xi. Unfortunately, this is very common for a vehicle to burn more oil as the engine ages. One thing you can do to combat the oil consumption is to use high...

Q: Ignition key won't come out of the switch.

Hi there. If the steering wheel lock is causing the key to say in the ignition system and also keeping the vehicle from starting due to the lock being stuck, then the steering wheel lock solenoid may not be working....

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...
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.