Check the listing for details. 1984-1996 C4 Corvette Knock Sensor Test Tool. Condition: New. Listed at 24.95 USD. 1984-1996 Corvette Knock Sensor Test Tool A fully functioning knock sensor is essential for maximum performance. It "listens" for engine knock often due to poor quality fuel. When it detects a "spark knock", it sends a signal to the ECM and an ignition timing correction is made to burn the fuel more efficiently. With the aid of the 1984-1996 Corvette Knock Sensor Tool and a digital voltmeter, you can easily test the knock sensor for peak performance. Instructions included. Allows for Easy Digital Volt/Ohm Meter TestingInstructions Included Click here for more C4 Electrical! Visit Mid America Motorworks eBay store for Corvettes! We offer over 5,500 Restoration Parts, Performance Upgrades and Personal Accessories for 1953-2020 Corvettes and Corvette Owners. FREE SHIPPING within 48 STATES. If shipping to: Alaska, Hawaii or Puerto Rico please email our eBay Store for a shipping quote. For shipping outside the US please use the eBay Global Shipping program. Thanks for looking!