Q: Coolant is leaking, but vehicle not overheating.

asked by on December 21, 2015

I have to keep filling the coolant in my vehicle every week. I cannot see the leak and the vehicle does not overheat.

Hello, a coolant leak with no external leaks leads me to believe you might have an internal leak at the head gasket. The first thing to do would be to check the oil and see if it looks like chocolate milk. If the oil looks ok, the next step would be to pressurize the coolant system, remove the spark plugs and see if coolant is entering into one of the cylinders. Unfortunately the coolant leak might also be temperature dependent and it may take some time to find it, some leak hot, some leak cold and some leak warm. To help, have you noticed that it might run a little rough at startup, like it has a misfire for a few seconds? If so, note the engine temperature and the amount of time the engine ran to get to this point. This information will help when pressurizing the cooling system and to determine which cylinder the head gasket is leaking into. You may need to enlist the aid of a mechanic to perform the above steps.

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

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

02 Cavalier overheating

You probably get the high quote because of your long list of problems. The overheating is the most serious symptom and is the one you need to look at first. It may be a simple as a leaking hose. The...

Transmission does not shift properly

Hi There, This can happen for a few different reasons such as low transmission fluid or a faulty control solenoid. An automatic transmission requires hydraulic pressure generated by the transmission fluid that gets pushed through a series of chambers inside...

Car misses and has a rough idle - 2001 Saturn L100

Hello. There are several things that could be causing your rough idle condition and therefore there are multiple possible solutions. Carbon buildup inside the intake manifold and valve train is a big cause of rough idle. This can usually be...

Related articles

Symptoms of a Bad or Failing Carburetor
Common signs include reduced engine performance, black smoke coming from the exhaust, backfiring, overheating, or hard starting.
A Buyer’s Guide to the 2012 Volkswagen Touareg Hybrid
Whether Whether you’re new to the hybrid wave or an old hat, the 2012 Volkswagen Touareg Hybrid gives you exactly what you’re looking for – a comfortable, luxurious ride that provides decent fuel economy. Key Features This hybrid option...
Is it Safe to Drive With a Cracked Radiator?
The radiator in your vehicle is used for cooling the internal combustion of the engine. Coolant is passed through the engine block, the heat...