How to Use Engine Coolant Test Strips

You can use engine coolant test strips to gauge your engine's pH level and use that knowledge to stop problems before they start. Thanks to engine coolant test strips, you'll know just how well prepared your engine is to face the common challenges of acid buildup, overheating and freezing.

  • Take note of what type of coolant you use in your car's engine before you shop for test strips. Though coolant colors are no longer used as universal-formulation codes, it wouldn't hurt to make a note of the color of the engine coolant you use as well.

  • Go to an automotive shop, where you'll be able to ask for help if you're unsure which types of test strips are compatible with the engine coolant you use. A person assisting you in the store will probably ask what kind of coolant you use or what color your coolant fluid is. Alternatively, you can find car-care supply websites for purchasing strips at AutoGuide.net (see Resources below).

  • Have a test strip with you as you open your car's hood to reveal the engine. Find the coolant chamber nozzle, and release it slowly. If you can feel any built-up pressure as you release the nozzle, be careful when you release it, as this can signal a buildup of hot radiator fluid, which might splash out and cause injury.

  • Dip the engine coolant test strip into the coolant chamber, ensuring that you immerse it for at least 30 seconds to 1 minute or as directed on the packaging. You need to submerge the strip and allow the coolant to seep in, so that it takes chemical action against the specially formulated compounds in your test strip.

  • Use the scaling guide, as provided on your particular product's packaging, to determine the pH level of your engine coolant. Most commercial engine coolant test strips will give readings in the following increments: six, seven, seven and one-half, eight and 11.

  • Speak to your mechanic about the correct action to take if you discover that your engine coolant's pH level is too high or too low. Generally, though, you can solve most minor problems with pH levels by draining and replacing the coolant fluid.