Q: Coolant reservoir empties in one trip

asked by on

I have a 2006 Camry with about 190,000 miles on it. A few days ago The engine heat gauge went high suddenly and when I looked the coolant reservoir was empty. I filled it and drove for half an hour. Next day I checked the reservoir out of curiosity but it was again empty. Ever since I have to fill the reservoir every time.

Now a few things to note: a couple of mechanics checked the engine but there is no visible leak, even the color dye added to the reservoir didn't appear anywhere and the engine has timing chain not belt. The exhaust has no smoke and is clear, even the mechanics said that. No one could given me a good reason for the complete lose of coolant from reservoir after every trip. What should I do? I need help.
My car has an automatic transmission.

If the radiator cap has failed (i.e. it doesn’t hold the specified pressure built up in the cooling system when the car is running), the cap will prematurely open while the car is running and coolant will flow into the reservoir and possibly overflow the reservoir (thus "losing" coolant).

Then as the engine cools after you turn it off, all available coolant is drawn back into the cooling system to make up for the overflow, thus lowering the level in the reservoir, or perhaps even emptying the reservoir if the cap failure continues over time.

That latter scenario is a possibility, but radiator caps can be tested if you have the right equipment.

If it the cap has already tested, and the cap tested good and there are no cracks (leaks) on the plastic coolant reservoir or loose connections, that confirms that you have an external or internal cooling leak (no mystery - there is a leak).

A standard test for exhaust in the coolant should be performed to see if perhaps the head gasket is leaking. Cooling systems on cars are not like working on the space shuttle...that is your cooling system is very limited in extent and there are very few "devices" involved (thermostat, radiator, some sensors, a cap, and so forth.) I’m really not sure why the shop you took it to was unable to find the leak.

At any rate, the thing to do is have an appropriate diagnostic performed. A professional from YourMechanic can come to your car’s location to pinpoint the coolant leak and have this problem repaired correctly.

Was this answer helpful?
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. Coolant reservoir empties in one trip

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: What does it mean when I put my car in gear and it won't move and makes loud clicking noise 2006 Chevrolet Malibu

Hello - check the fluid level and quality (should be more pink than black, and not smelled burned). Check also the shifter cable - the inability to re-engage Park (which is a mechanical action) suggests the shifter is no longer...

Q: Vehicle overheated poor ac cooling and gas mileage

Hi there: Changing the radiator, hoses and thermostat does not typically negatively impact fuel economy or AC issues. However, the installation of those items might, especially if the serpentine belt was installed incorrectly. However, with Hybrid models, the two issues...

Q: Q: Purge valve location

The vapor vent valve is located on air inlet tube between the throttle body and the mass air sensor. It is mounted on side of the air tube.

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
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...