Fault Phenomenon: SANY SY215 excavator black smoke from exhaust during acceleration, digging power low.

Troubleshooting Process:
– Checked air filter: air filter severely clogged.
– Checked turbocharger: insufficient boost pressure.
– Checked injector nozzles: poor atomization.
– Checked timing: injection timing too late.

Root Cause: The air filter was not replaced for a long time, causing high intake resistance and incomplete combustion, leading to black smoke.

Required Parts: Replace air filter element.