Order before 16:00 on business days? Shipped the same day!

Fast & reliable shipping throughout Europe

Expert customer service with professional advice

Mega Sale: Discounts up to 75%! While supplies last!

View Offers
Discover similar products: Autool, Spark Plug Testers
Autool  |  SKU: SPT101

Autool SPT101 | Spark Plug Tester

€28,95 incl.
€23,93 excl.

Warranty directly via AsTools

We handle warranty cases ourselves, quickly and without involving the manufacturer. Thanks to our own parts inventory and technical expertise, we can usually assist you immediately. Only in exceptional cases do we still send the product to the supplier.

2 years warranty on all products

All our products come with a 2-year factory warranty. This ensures you long-lasting quality and service.

Easy returns

You can easily request your return through your account. We will send you the return label by email. Return shipping costs are your responsibility.

Professional customer service

Our experts are ready to help you quickly and professionally, both online and in our physical store. Questions? Feel free to contact us!

The Autool SPT101 is a stationary spark plug tester that is designed for diagnosing spark plugs outside the engine block. Within the ignition system is correct spark plug operation essential for efficient combustion. This tool enables visual inspection of the spark plug ignition under simulated engine conditions. The tester is specifically designed for diagnosing 12V petrol engines in cars and motorcycles, allowing the performance of individual spark plugs to be reliably and consistently assessed.

The tester works by detecting the operation of a ignition coil to simulate and internally generate a high voltage that is applied directly to the spark plug is displayed. This allows for a clear visual assessment of the spark strength and enables smooth transition. The device features an adjustable operating frequency which reproduces an engine speed of 500 to 6000 revolutions per minute. During operation, spark plugs are inserted into the test ports, allowing you to safely observe the spark discharge through the transparent protective cover to detect internal breakdown or weak spark performance.

KEY FEATURES

✔Two test ports side by side — Test two spark plugs at the same time, so you can directly compare a suspect plug against a new reference plug.
✔Infinitely adjustable operating frequency for simulating engine speeds up to 6000 revolutions per minute.
✔Equipped with a clear protective cap for safe observation of spark discharge under high voltage.
✔Works completely independently — With the built-in high-voltage generator, you can test spark plugs on the workbench without needing a vehicle or ignition coil.

KEY FEATURES

✕Exclusively designed as stationary tester; the spark plugs need to be removed from the engine block.
✕Requires mains power via the adapter from 100 to 240V; the device is cannot be powered directly from the vehicle battery.
✕Designed for spark plugs in gasoline engines only — Glow plugs from diesel engines operate on a different principle and cannot be tested with this device.
✕Spark plug electrode diameter from 11 to 12 mm — Spark plugs with non-standard sizes will not fit the test ports.

Application and functionality

This benchtop spark plug tester is designed for precise and safe visual inspection of removed spark plugs.

  • Frequency control: Allows you to adjust the ignition frequency between 500 and 6000 RPM using the dial, so you can verify that spark discharge remains stable as engine load increases.
  • Dual test port: Enables simultaneous testing of two spark plugs. In practice, this is useful for comparing a worn spark plug directly with the spark pattern of a new reference plug.
  • Visual spark inspection: Lets you assess the color, thickness, and path of the ignition spark to identify internal short circuits, worn electrodes, or insulator cracks.

Special features and capabilities

The device is built with specific hardware designed to generate high voltage at the workbench.

  • Internal high-voltage generator: The tester features an integrated coil that converts the supply voltage into the high voltage needed to create an arc across the spark plug electrodes, independent of the vehicle's ignition system.
  • Transparent safety shield: Equipped with a hinged cover that fits over the test ports. This protects the technician from accidental contact with high-voltage components during testing.

Compatible vehicles and ignition systems

This diagnostic tool is engineered for universal use with standard ignition systems on internal combustion engines.

  • Vehicle category: Passenger cars, light commercial vehicles, and motorcycles.
  • Ignition system: 12V gasoline engines equipped with standard spark plugs.
  • Diagnostic application: Benchtop testing of spark strength and spark plug behavior with electrode diameters from 11 mm to 12 mm.

Package contents

  • 1x Autool SPT101 spark plug tester
  • 1x AC power adapter
  • 1x User manual
💡
Good to know: Always switch off the tester's power supply completely before inserting or removing spark plugs from the test ports to avoid high-voltage contact. Also, don't judge the spark only at low RPM: a worn spark plug often produces a clean spark at 500 RPM but fails at higher speeds. Turn the frequency up to maximum and watch for the moment when the discharge becomes irregular.

Technical Specifications

Specification Description
Product Brand Autool
Product Model SPT101
Product Type Stationary spark plug tester for bench use
Number of Test Ports 2, can be used simultaneously
Simulated Engine Speed 500 to 6000 RPM
Compatible Spark Plug Diameter 11 mm and 12 mm
Suitable For Spark plugs for 12V petrol engines
Power Input 100 to 240V AC
Power Output 12V DC, 1A
Safety Feature Hinged transparent protective cover
Device Dimensions 145 x 110 x 85 mm
Device Weight 354 grams
Item Number SPT101