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Q: Coolant leaking from top of coolant tank

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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.

A: You either did not get the coolant cap tigh...

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.

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