Dec 25, 2025
The CP4 pump, a Bosch high-pressure fuel injection pump used in many modern diesel engines like Ford Powerstroke and GM Duramax, is prone to failure due to inadequate lubrication from ultra-low sulfur diesel (ULSD). This causes internal wear, metal shavings, and often catastrophic contamination of the entire fuel system. Read more to understand symptoms, causes, and prevention strategies. Learn more: Causes of CP4 Pump Failure