Skip the auto shop - Our mechanics make house calls

Q: Radiator keeps blowing coolant back into holding tank

asked by on

I changed the thermostat and the coolant keeps getting pushed back into the holding tank. The temperature stays cool now, but can't keep coolant in the radiator.

My car has 103000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. This is a sign t...

Hi, thanks for writing in. This is a sign that you may need to have the radiator system burped. This is a process that is used to relieve the air in the system which can cause the coolant to overflow into the holding tank as you describe. In the event that the car is overheating, this may also cause this kind of problem, but the overheating is a much larger issue that will need to be addressed as well. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect this situation for you, and make or suggest any services or repairs as needed.

Was this answer helpful?
Recommended services
Get a Quote

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: Expansion tank cap keeps cracking and the car overheats in stop and go traffic.

It is impossible to tell without doing some further testing. Your issue may be caused by a compilation of several different components. A run of 6 months is pretty good to not have any issues. Slow traffic can cause the...

Q: Replaced the fuel injectors and car won't turn over.

Hi there. I totally understand your frustration, as for the life of me, I can't understand why somebody would bypass the fuel filter. However, it is quite possible that the two issues are not related. If a car won't start,...

Q: I have an Audi A6 Quattro the problem is when im driving the car is over heating 2003 Audi A6 Quattro

Hello - if you can drive for almost 45 minutes without the car overheating, the problem is more likely a clogged radiator or weak water pump. A blown head gasket is a remote possibility as well. A malfunctioning thermostat will...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
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...
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.