Fault Phenomenon: Caterpillar 793 mining truck engine power is limited, exhaust back pressure is high, instrument indicates Diesel Particulate Filter (DPF) clogged.

Troubleshooting Process:
– Checked DPF: excessive soot accumulation, regeneration failed.
– Checked injector: post-injection injector faulty causing insufficient regeneration temperature.
– Checked sensor: exhaust temperature sensor failed.
– Checked fuel: high sulfur content in fuel.

Root Cause: Prolonged low-load idling operation caused exhaust temperature to be insufficient to trigger active regeneration, leading to soot clogging inside the DPF.

Required Parts: Perform forced stationary regeneration; replace DPF assembly if ineffective.