Skip the auto shop - Our mechanics make house calls

Q: Leaking radiator cap

asked by on

I noticed my car engine smoking from the front, when I checked I saw that coolant had been leaking from the cap then down the back face of the radiator causing the smoke I'm assuming. My overflow tank had been drained down to the minimum line so I refilled it and a few days later it was empty again. My car only starts smoking when the overflow is filled and stops when its near empty. My temperature gauge on my dashboard has not gone past half way where it always goes up to so I;m assuming my car is not over heating. I just want to know why that is happening and what to do to fix it.

My car has 225000 miles.
My car has an automatic transmission.

Hello there:

Most of the time, the smoke you see coming from the front of the vehicle that has a coolant leak from the radiator cap is steam. This is an indicator that the radiator cap needs to be replaced; as it’s not maintaining a solid vacuum; which could eventually cause air bubbles to be trapped in the coolant lines and eventually overheat the Toyota. If the overflow reservoir is draining, it’s because it’s trying to fill the evaporating coolant caused by the radiator cap in this instance most likely. If you replace the radiator cap first and this doesn’t solve your issue, contact one of our professional mobile mechanics to complete a car is leaking coolant inspection.

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
  1. Home
  2. Questions
  3. Leaking radiator cap

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: Dodge 95 van in the freeway and oil arm on dash board drops all the way to l.

The oil pressure light will usually come on when a few things could be happening. Either the motor is in fact low on oil, the oil pump could be failing or not pumping oil sufficiently or the oil pressure sending...

Q: White smoke

If there is thick white smoke coming from the exhaust, it can be the sign of a failed head gasket. You will see white smoke from the exhaust during very cold weather as well, which does not always mean there...

Q: Why would there be gas leaking from underneath the car?

This sounds like potentially a problem related to the fuel tank venting or possibly a leak in the tank itself. This is a difficult problem to diagnose without testing the tank for leaks. Because this can be very dangerous if...

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...
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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...