LF0118921 Mazda SENSOR,KNOCK, Price: 36.11$, Weight: 0.06kg

Engine Knock Detection Sensor for Mazda Vehicles

This ignition safety sensor is fitted to the engine block to “listen” for abnormal combustion (pinging/knocking). It’s needed because modern Mazda engines run tight fuel and timing control for power and fuel economy, and any uncontrolled detonation can quickly damage pistons, rings, and bearings.

How It Works ?

Inside is a piezoelectric element that converts vibration into an electrical signal. The ECU reads this signal and, when knock is detected, retards ignition timing and adjusts fueling to protect the engine. When conditions improve, timing is restored for normal performance.

Symptoms If It’s Faulty ⚠️

A failed unit or poor connection may cause loss of power, sluggish acceleration, higher fuel use, rough running, or a check engine light. In some cases the ECU may run overly conservative timing, while real knock can go unnoticed.

Why Replacement Matters ✅

Driving with a bad knock signal risks long-term engine damage from detonation or constant reduced performance. Replacing the sensor restores correct timing control, smoother driving, and safer combustion under load.