Cold Start Engine Coolant Pump Performance
During cold start, the engine coolant pump does not produce the expected flow. Pump aging combined with high cold viscosity, or pump-disable strategy malfunction.
Affected components
- Engine coolant pump
- Engine coolant loop
Common causes
- High likelihood: Pump output degraded with age
- Medium likelihood: Cold coolant viscosity too high
Diagnostic notes
- The malfunction indicator lamp may illuminate
- A drive cycle may be required after repair
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.