Best Compression Testers: Diagnose Your Engine with Ease

Test your engine’s capabilities quickly and efficiently with these top-rated compression testers

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Has your check engine light ever flickered on and you’re not sure why? You could take it to a mechanic, but he may overcharge you just to diagnose the problem. Or you could use a compression tester to discover what’s wrong. The tool diagnoses problems in the engine and alerts you of any dangers or mechanical failures. In this buying guide, we highlight the best compression testers on the market.

  • Best Overall
    Innova Compression Tester
    Summary
    Summary
    This versatile gauge works on electronic and computerized domestic or import vehicles. It features a 15-inch-long rubber hose, three-valve adapters, and a side release valve.
    Pros
    Pros
    It features a large dial face with an easy-to-read meter and a durable rubber hose. Plus, it has dual-calibrated and color-coded scales. The device also functions on motorcycles, ATVs, snowmobiles, and marine vehicles.
    Cons
    Cons
    You may need adaptors to connect it to certain vehicles such as motorcycles and ATVs to connect it to the spark plugs. It also does not come with a carrying case.
  • Best Value
    8MILELAKE Professional Petrol Gas Engine Cylinder Compression Tester
    Summary
    Summary
    This compression tester comes with two rubber cone ends that make for a faster and more convenient connection. It also features four different fittings and two spark plug adapters.
    Pros
    Pros
    The 3-inch gauge is easy to see and read with its dual color scale. Another nice feature is the inclusion of a quick push-button pressure release valve. One of the best additions is its tough and sturdy carrying case.
    Cons
    Cons
    The pressure release may not relieve pressure quick enough, but that doesn’t ruin the design. Plus, the adapters may not be compatible with all types of vehicles, so you may need to order extra adapters.
  • Honorable Mention
    PMD Products Compression Gauge Test Set
    Summary
    Summary
    This engine compression tester comes in a rugged blow mold case to keep it safe and secure. The set comes with a 3-inch dual scale gauge with a push-button release.
    Pros
    Pros
    The kit also includes four fitting sizes and two spark plug adapters with two rubber cone ends and a 14-inch-long rubber extension hose. All of this makes it simple to use and quick to connect.
    Cons
    Cons
    When checking the engine, the device may read around 10 pounds lower than normal. The rubber seems a bit flimsy and may tear or get caught more easily in tight spaces.

Tips

  • It’s best to have a dedicated space to store the compression tester and its components. If it doesn’t come with a case, you can either buy one for it or store it in a toolbox.
  • It is always wise to have multiple adapters for your compression tester. Not every vehicle is created the same, so owning different adapters at various lengths will ensure you can check a number of vehicles.
  • A small amount of condensation or dirt can interfere with the device, causing it to produce incorrect readings. Always place every part and the tester in its protective case, and store it somewhere dry and cool.

FAQs

Q: Will a compression tester work on gasoline and diesel engines?

A: A compression tester will work on both types of engines. They are designed to test spark plugs and injector sockets in your engine to measure the amount of pressure in the engine.

Q: How does compression tester work?

A: The compression tester comes with a hose that connects to the spark plug hole of each cylinder. The gauge then hooks up to the opposite end of the hose. After turning on the engine, the needle will climb to a certain number that you need to keep track of. After doing this for each cylinder, all the readings should be similar or within 10 to 15 percent of each other.

Q: What PSI should my engine be registering?

A: Each cylinder should register at 100 or more PSI to be considered healthy. A good target goal should be around 180 to 220 PSI.

Final Thoughts

For a high-quality compression tester with a selection of adapters and long hose, consider the Innova Compression Tester

Or there’s the 8MILELAKE Professional Petrol Gas Engine Cylinder Compression Tester, which comes in a handy carrying case with plenty of adapters at a cheaper price.