Purpose
To inspect engine and control system for damage
(leaks, open connections, or harness chaffing)
Tools
• Inspection lamp
Procedure
1. Inspect fuel supply system (including tank and lines) for leaks and damage.
2. Check high-pressure oil line from high-pressure pump to supply manifold for major leaks.
3. Check engine for oil leaks.
4. Inspect cooling system for leaks.
5. Check sensor, relay, and control module connections. All connections must be seated, in good condition, and free of damage or corrosion.
NOTE: The engine will not start if the following components are disconnected or damaged:
• Injection Pressure Regulator (IPR) valve
• Camshaft Position (CMP) sensor
• Crankshaft Position (CKP) sensor
• Electronic Control Module (ECM)
• Injector Driver Module (IDM)
6. Inspect battery cable and fuse connections for corrosion. All connections must be seated, in good condition, and free of damage or corrosion.
7. Inspect engine wiring harness for correct routing and protection against rubbing or chaffing.
8. Check the following components of the air induction system for leaks:
• Inspect air filter housing for damage or distortion that could allow unfiltered air into the engine.
• Inspect air filter housing for end seal movement. End seal movement is indicated if the seal contact area is polished. A polished contact area indicates that unfiltered air has passed by the filter element and into the engine.
• Inspect air filter element for end cap dents, holes, damaged seals, and soot.
• Inspect air intake hoses and clamps for tightness and positioning over sealing beads.
• Inspect the chassis mounted Charge Air Cooler (CAC) and piping.
NOTE: Unfiltered air will cause accelerated engine wear.
9. Record identified problems on Diagnostic Form.
• If problems were identified, repair as necessary and verify if a hard start and no start condition still exists.
• If no problems were identified, continue with the next diagnostic test.
Possible Causes
• Loose or leaking fuel supply lines could cause fuel system to lose prime.
• Kinked or blocked fuel supply lines can restrict fuel flow.
• Massive or excessive fuel or oil leaks
• Coolant leaks could indicate serious engine damage.
• Damaged or incorrectly installed electronic connectors
• Blockage in the air induction system
