6 Best Spark Plug Reading Tips for 2026
Want cleaner spark plug diagnostics in 2026? Start with a sealed viewing tester that fits your 6 to 12V system, then check plug fit, boot size, and coil style before blaming the engine. Use a calibrated 0.001 to 0.002 in feeler gauge to set the gap, and watch for carbon buildup, rounded electrodes, or bent tips. With the right tools and a quick visual check, you can spot problems faster and cut down on garage guesswork.
