Vehicles using OM602 engine list:

Engine OM602

Symptoms:
- Hard starting or failure to start
- Rough idling and loss of power
- Excessive smoke from exhaust (black or white)
- Oil leaks around valve cover or oil cooler
- Overheating or coolant loss
- Unusual noises such as knocking or ticking

Diagnosis:
- Check glow plugs and relay for proper operation, especially in cold conditions
- Inspect fuel injection pump and injectors for wear or clogging
- Examine valve cover gasket and oil cooler seals for leaks
- Test coolant system for leaks and thermostat function
- Listen for abnormal engine noises indicating timing or bearing issues
- Perform compression test to assess cylinder health

Fixes:
- Replace faulty glow plugs and repair glow plug relay wiring
- Clean or replace fuel injectors and service injection pump as needed
- Replace valve cover gasket and oil cooler seals to stop oil leaks
- Flush cooling system, replace thermostat, and repair leaks to prevent overheating
- Adjust valve clearances and timing belt if worn or noisy
- Address any bearing or internal engine damage promptly to avoid further failure

Prevention:
- Use high-quality diesel fuel and change fuel filters regularly to protect injectors
- Maintain regular oil changes with recommended grade oil to prevent sludge and wear
- Monitor coolant levels and condition, replacing coolant per manufacturer schedule
- Inspect and replace timing belt at recommended intervals to avoid catastrophic failure
- Address minor leaks and noises early to prevent major engine damage
- Store vehicle in a dry environment and run engine periodically if unused for long periods

By following these diagnostic steps and maintenance practices, owners of vehicles equipped with the OM602 engine can ensure reliable performance and longevity.