Q: Coolant leaking from top of coolant tank

asked by on

I was driving one day and when I came home and parked my car a few hours later noticed a very small puddle of coolant on the ground. Popped the hood and saw that the coolant was low. Top it with with some water and left it. A week later I was driving and noticed the temp gauge was fluctuating above 50%. I went to gas statioN to get gas and all my coolant started leaking out of nowhere. Popped open the hood and the cap was loose but still on and all the coolant had overflown out of the tank and down the sides.

My car has 70000 miles.
My car has an automatic transmission.

You either did not get the coolant cap tightened completely when you topped it off before or you have a defective cap. Replace the cap and refill the system while making sure the cap is on all the way. If the problem persists and you suspect something is wrong, then have a certified mechanic, like one from YourMechanic, diagnose the coolant leak firsthand for you. Good luck.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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!
  1. Home
  2. Questions
  3. Coolant leaking from top of coolant tank

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: Car is overheating, usually when it's hot and the engine idles.

You most likely have a transmission cooler that is leaking into the coolant inside the radiator. The transmission cooler is built inside the side tank of the radiator, and if it blew out, then you will have transmission fluid getting...

Q: When turning left or right clinking noise in the front.

Lift the hood and have someone turn the wheel back and forth while you feel the top of the strut under the hood and listen and feel for the upper strut bearings making noise. They may need to be replaced....

Q: Leaking clear but oily fluid when AC is running. It is located through the front end under the hood (by the aluminum cover insulation in front)

Hello. From what you describe, it would appear that your vehicle may possibly have a refrigerant leak in the AC system. I would carefully inspect the area where the fluid is coming from to see if you can figure out...

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...
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.