Q: Coolant Leak

asked by on June 01, 2016

Car has never overheated or had any cooling system problems until the other day. Suddenly it said "coolant low, stop engine". While it's sitting or idling, the coolant stays put unless the coolant reservoir tank cap is removed. I filled it up, tightly put on the cap and took it for a drive and suddenly all of the coolant was drained again. I would appreciate any advice on why it only drains while I'm driving and what it could be.

My car has 140000 miles.
My car has an automatic transmission.

Coolant is leaking Inspection $94.99 - $114.99 Get a Quote

Hi there. The coolant can disappear for a number of reasons. The most common being an external leak. If it is not obvious as to where it is coming from then the system needs to be pressure tested. The water pump is a common place for it to leak without showing any leakage as the vehicle sits.

If there are no external leaks, then I typically do a block test, as a leaking head gasket can cause this; it will draw coolant into the combustion chamber and burn it off.

If you plan on having it repaired, consider using YourMechanic, as a certified mechanic can come to your home or office to diagnose your coolant leak.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Car won't start after repair work
Hello there. If the engine is cranking and not starting, and the security light is on, then the security system may be having problems. This does not necessarily mean that he caused this. Most of the time, this is caused...
Key fobs not working
Hi there. A lack of communication between your key fobs and your vehicle can point to the receiver that detects your key in its presence. Also, your key fob battery itself can be completely dead or no longer be communicating...
Brake lights
If you did not check the bulbs themselves before changing the brake light switch, you might want to start there. Blown brake light bulbs (https://www.yourmechanic.com/services/brake-light-bulb-replacement) can actually cause the ESC light (https://www.yourmechanic.com/services/brake-warning-light-is-on-inspection) to come on, so make sure that the...
Steel hose leaking antifreeze - 1992 Plymouth Acclaim V6
Hi there, thanks for your question. If the pipe is leaking coolant, it must be some type of cooler line or coolant bypass hose. There are several terms for these and it can be confusing finding the right parts. Sometimes...
what dose it mean when your Mercedes Benz R class 350 is displaying restrained system malfunction and service E. exceeded 141 days
"Service E exceeded by 141 days" indicates your vehicle is overdue for s Service E. Check with your owner's manual or dealership service department as to what is included in a Service E. Once you find out what is included...
Vibration when 65+mph or when stoping
Whenever there are multiple causes of vehicle vibration, which is probably the circumstance you face, it is best to fix the obvious causes first because that will greatly simplify diagnosis and identification of the remaining causes. So, in your circumstance,...
Can't find ebrake release
Hello. On this particular vehicle the e-brake will not engage the standard way of pushing it all the way to the floor after it is engaged to make it release. There will be a little lever to the left of...
The vehicle makes a humming/whining sound immediately after highway driving. After several minutes off highway, noise stops.
Hello, thank you for writing in. There are several issues that may cause these issues. You will want to start by making sure the brakes are not sticking. This can be done by raising the vehicle and checking for grinding...
I have a 2011 Chevy Equinox with 150,000 miles on it. The check engine light and Service engine soon light both came on. I brought
There is only one oil control solenoid, per camshaft, in the variable valve timing (VVT) system. If both mechanics are referring to a solenoid or solenoids in the VVT system, then they are necessarily referring to the identical part. If...

Related articles

Symptoms of a Bad or Failing Stay Rod
Common signs your classic car has a failing stay rod include rattling noises from the front and a radiator that looks tilted or about to fall.
How Long Does a Universal Joint (U-Joint) Last?
For For most rear wheel drive cars, a driveshaft is needed to ensure that the tires turn as they should. The driveshaft works by taking the power from the transmission and transferring it to the wheels of the vehicle. In...
Understanding Volvo Service Reminder Indicator Lights
Car symbols, or dashboard lights, are a car service reminder. The Volvo Service Reminder Indicator lets you know when your car needs service.