Airtex 5S2166 Ignition Knock (Detonation) Sensor

The Airtex 5S2166 knock sensor (also called a detonation sensor or engine knock sensor) is a replacement ignition component that monitors engine vibration and reports abnormal combustion, known as knock or detonation, to the engine control unit. Using this signal, the ECU can adjust ignition timing to help protect the engine and keep it running efficiently.

Key Features:

• Sintered piezoceramic sensing element, which Airtex says greatly reduces the fractures that cause many original-equipment knock sensors to fail early
• Extra-strength epoxy holds the piezo element in place for durability
• Overmolded plastic body that resists age- and heat-related shrinkage
• Premium silicone internal seals designed to keep moisture out
• Trivalent iridescent chromate plating on the sensor to resist corrosion

Interchange / Cross-Reference: Airtex 5S2166 is listed as an interchange for Standard Motor Products KS115, ACDelco 213-924 and 21024981, GM 21024729 and 21024981, Walker Products 242-1051, and Kem 144-430.

A failing knock sensor can cause a check engine light, reduced power, poor fuel economy, or engine pinging. Replacing it with the Airtex 5S2166 helps restore proper knock detection and engine management.