Engine Crank Angle Sensor (Crankshaft Position Sensor)

This sensor is a key input for the ECU to control ignition timing and fuel injection. It reads the exact crankshaft speed (RPM) and position, so the engine can fire each cylinder at the right moment. Without a clean crank signal, even a strong engine will act like it “lost its rhythm”.

How it works ⚙️

The sensor monitors a toothed trigger wheel on the crankshaft. As teeth pass the sensor tip, it generates a pulse signal. The ECU counts these pulses to know crank angle and uses them to synchronize spark, injector pulse, and misfire detection. Accurate feedback improves starting, smooth idle, and proper power delivery.

Why this part is needed ✅

• Ensures fast starts and stable idle
• Keeps correct ignition/injection timing under load
• Helps prevent stalling and random cut-outs

What happens if it fails

A failing unit may cause hard starting, sudden stall, no-start condition, rough running, weak acceleration, or a check-engine light. In many cases the ECU cannot safely time spark/injection, so the engine may crank but not fire. Prolonged driving with an unstable crank signal can lead to misfires and fuel waste.

Compatible Models

• Q30/Qx30
• Q70/M
• Qx70/Fx
• Qx50/Ex
• M