Hi, no it's not for clamping on, it's for detecting for a spark and so you just touch it on the ht lead

does it work on small engine 4-cycle, 12V

Our Service dept use this all the time on small engines. You do have to properly adjust the dial on the unit for small engines. We use as a quick test.

does this actually detect if the plug wire is pulled loose from the plug itself?

Probably not, but a good visual inspection should. I use it to narrow down suspect cylinders that have a misfire such as a defective coil or wire. I have also found plugs that arc inside the plug boots.

Will this work on fuel injectors ?

No- Just ignitions. Fuel injectors are low voltage.

Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

Help Track order

Account Cart

Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

Help Track order

Account Cart

Calterm 66331 Tru-Spark Ignition Firing LED Indicator, Adjustable Sensitivity

Calterm 66331 Tru-Spark Ignition Firing LED Indicator, Adjustable Sensitivity

Product ID: 341059989

Details

Brand
Calterm
Colour
Red
Item dimensions L x W x H
5.6 x 15 x 3.6
Power source
Battery
Style
Modern

💡Dual LED indicators for real-time status feedback

🎚️Adjustable sensitivity dial for pinpoint accuracy

🛡️Rugged ABS housing resists oil & shop wear

Description

⚡ Ignite your diagnostics with precision and confidence!

NON INVASIVE TESTING - Detects secondary voltage without piercing or removing spark plug wires, preserving system integrity and saving time.
INSTANT VISUAL FEEDBACK - Green LED confirms tester readiness; red LED flashes with each ignition pulse for clear, immediate insights.
BUILT FOR HARSH ENVIRONMENTS - Durable high-impact ABS casing withstands oil exposure and tough workshop conditions without fail.
PRECISION SENSITIVITY CONTROL - Exclusive dial isolates specific plug wires, eliminating false signals and boosting diagnostic confidence.
UNIVERSAL IGNITION COMPATIBILITY - Seamlessly tests both DIS and conventional ignition systems—your all-in-one ignition troubleshooting tool.

The Calterm 66331 Tru-Spark Ignition Firing LED Indicator is a professional-grade tester featuring an exclusive adjustable sensitivity dial to isolate plug wires and prevent false readings. Equipped with dual LED indicators for operational status and ignition pulse detection, it’s housed in rugged ABS to endure demanding shop environments. Compatible with both DIS and conventional ignition systems, it enables quick, non-invasive voltage testing to streamline troubleshooting and ensure reliable ignition performance.

Specifications

Asin	B000JFHMPC
Best Sellers Rank	#7,594 in Automotive (See Top 100 in Automotive) #2 in Automotive Ignition Testers
Brand Name	Calterm
Color	Red
Compatible Devices	Ignition systems (DIS and conventional)
Customer Reviews	4.2 4.2 out of 5 stars (355) 4.2 out of 5 stars
Global Trade Identification Number	00046494020230
Item Dimensions	5.6 x 15 x 3.6 centimeters
Item Type Name	LED Indicator
Manufacturer	Calterm
Measurement Type	Voltage
Model	66331
Number Of Items	1
Part Number	66331
Power Source	Battery Powered
Specification Met	CE, ETL, RoHS, UL
Style Name	Modern
Unit Count	1.0 Count
Upc	971473127474 046494020230 521227771189 956257381846

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Sneha T.

Received my product in pristine condition. Great service overall.

1 month ago

Yusuf A.

Fantastic experience overall. Will recommend to friends and family.

1 month ago

View all Trustpilot reviews

Shop Global, Save with Desertcart

Value for Money

Competitive prices on a vast range of products

Shop Globally

Serving millions of shoppers across more than 100 countries

Enhanced Protection

Trusted payment options loved by worldwide shoppers

Customer Assurance

Trusted payment options loved by worldwide shoppers.

Desertcart App

Shop on the go, anytime, anywhere.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Anjali K.

The product quality is outstanding. Exactly what I needed for my work.

1 month ago

Rajesh P.

Customer service was outstanding when I had questions about the product.

2 days ago

View all Trustpilot reviews