(Upgraded SP02) ANCEL SP20 Spark Plug Tester

The ANCEL SP20 is a dual-socket, one-button spark plug tester that lets you visually compare spark performance on 12V gasoline engines safely through a clear protective cover.

If you troubleshoot rough idles, hard starts, misfires or poor acceleration, a fast visual check of spark quality can save time and parts. The SP20 provides a simple, repeatable way to inspect two spark plugs side-by-side under the same simulated conditions, so you can spot weak or intermittent sparks before replacing ignition components.

How does the ANCEL SP20 reveal weak or failing spark plugs?

By creating a controlled gap and allowing you to observe the electrical discharge, this tester shows spark intensity and stability visually. Comparing sparks makes it easier to detect reduced voltage output, inconsistent firing, or arcing that indicates aging or damaged plugs.

• Dual sockets let you test two plugs simultaneously for direct comparison.
• Visible spark window shows intensity, color and consistency of discharge.
• One-push activation produces a repeatable test without engine RPM adjustments.

Is the SP20 safe and simple enough for home mechanics?

The unit includes a transparent protective cover that helps isolate the high-voltage area while keeping the spark visible, reducing the risk of accidental contact. Operation is straightforward: insert plugs, close the cover, press the button, and observe the result — no complex setup or tuning required.

• Clear cover protects the user while allowing visual inspection.
• Single-button control removes need for technical adjustments.
• Compact footprint works on a garage bench or workbench safely.

Which engines and spark plugs does this tester work with?

The SP20 is designed for standard spark plugs used in 12V gasoline engines, covering cars, motorcycles, ATVs, lawn mowers, generators and most small-engine equipment. It accepts plugs with an insulator diameter up to 13 mm; very short plugs may not fit properly.

• Compatible with most 12V gasoline engine spark plugs (up to 13 mm insulator).
• Suitable for automotive, powersports and small engine maintenance.
• Not intended for exceptionally short spark plugs — verify size before testing.

What practical benefits will I notice during diagnostics?

Using the SP20 speeds up troubleshooting by showing whether a plug produces a strong, steady spark or is weak and erratic. That clarity helps you decide whether to clean, gap, or replace plugs and prevents unnecessary part swaps that increase repair time and cost.

• Quickly isolates ignition-related problems during routine checks.
• Helps compare new versus aged plugs under identical conditions.
• Reduces guesswork, saving both diagnostic time and replacement parts.

Who is this for: The ANCEL SP20 is made for DIY enthusiasts, home mechanics and professional technicians who service 12V gasoline equipment and want a fast, visual way to evaluate spark plug performance. It’s useful for anyone maintaining cars, motorcycles, ATVs, lawn mowers, generators or small engines who needs a compact, easy-to-use tester to confirm spark condition before investing in replacements or more invasive repairs.