Fault Phenomenon: Schwing S365 engine runs smoothly when cold. While idling (operating temperature), the engine vibrates violently, exhaust is uneven, and eventually stalls.

Troubleshooting Process:
– Checked engine mounts: not aged, no breakage.
– Checked injectors: bench test shows normal atomization.
– Checked cylinder compression pressure: pressure even across cylinders.
– Measured crankshaft position sensor signal at operating temperature: found missing tooth on signal.

Root Cause: The crankshaft position sensor magnetic tip demagnetizes due to heat, causing signal loss and ignition misfire.

Required Parts: Crankshaft position sensor.