Skip the auto shop - Our mechanics make house calls

How to Find the Source of a Coolant Leak Faster and More Accurately

How to Find the Source of a Coolant Leak Faster and More Accurately

Coolant is vital to your engine. A mixture of coolant and water circulates through the engine to absorb heat. The water pump circulates it in a loop past the thermostat, through coolant hoses, to the radiator to be cooled by air movement and then takes it back through the engine. If your engine runs low or is completely out of coolant, the overheating that results can cause irreparable damage to your engine.

Always check the coolant each time you check your the oil level in your car. If you’ve started to notice the level dropping between check- ups, it’s time to find out where the leak is occurring. If there is a coolant leak, you may see a puddle under the car or start noticing a sweet smell coming from the engine compartment after a drive.

Part 1 of 1: Find the source of the coolant leak

Materials Needed

Step 1: Do a visual check of the radiator, hoses and around the engine. Your vehicle has an upper and lower radiator hose, heater hoses at the back of the engine connecting to the heater core, and probably a couple of other smaller hoses going to the intake manifold or throttle body area. If a visual inspection reveals nothing, move on to the tried and true method of using a pressure tester.

Step 2: Use a pressure tester. Attach the pressure tester in place of the radiator cap.

  • Tip: If you don’t have a pressure tester or want to purchase one, some chain auto part stores offer tool rentals.

  • Note: The radiator cap will have a pressure rating on it. When you apply pressure with the pressure tester, be sure not to exceed that pressure on the dial. Always apply pressure to the cooling system with the engine off.

Step 3: Check again for a leak. Once pressurized, do a visual check around the engine bay once again. Be sure to check all the hoses, radiator itself, and all the coolant hoses and temperature sensors on or around the intake manifold. You most likely will find the source of your leak now.

If you are not comfortable with performing this check on your own, you can get your coolant leak inspected by a certified professional from YourMechanic.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...


Related questions

Q: Car is leaking coolant, and overheating, is it the intake manifold gasket?

This may be related to a few different things such as a bad thermostat, a failing coolant fan relay, or a blown head gasket. As you may know the thermostat regulates the flow of coolant in and out of the...

Q: the engine has a melattic rattleing sound and oil leaking

Hello, thank you for writing in. The noise may be related to the oil leak. Low oil pressure and lack of lubrication to the engine causes a large number of engine components to wear quickly and rub when they should...

Q: car code

Diagnostic Trouble Code P0170 means that your engine computer (PCM) has had to adjust the fuel trim (fuel supply), high or low, but to the extent that the adjustment is out of the "normal" range. This adjustment that the PCM...