Purpose
To determine the following:
• Does the crankshaft rotate?
• Does the instrument panel receive a signal from the Electronic Control Module (ECM) and is rpm sufficient?
• Is oil pressure sufficient?
• Is fuel getting into the cylinders?
Tools
• None
Procedure
1. See “DT 466 Performance Specifications” – Appendix A (page 595) or “DT 570 and HT 570 Performance Specifications” – Appendix B (page 619) for specifications, and enter data in spec column for rpm and oil pressure on Diagnostic Form.
2. Turn the ignition switch to START.
NOTE: If equipped, push optional push button to crank engine.
3. Check rpm on instrument panel. Record results on Diagnostic Form.
• If engine speed is below specification, the engine will not start. Check batteries and DTCs if engine seems to be turning over fast enough to start and no rpm is noticed on instrument panel.
4. Check oil pressure (instrument panel). Record results on Diagnostic Form.
• If oil pressure does not build while cranking the engine, oil may not be feeding the high-pressure oil system. Check oil level.
5. Check for exhaust smoke and record color on Diagnostic Form.
NOTE: Typically smoke indicates that fuel is getting into the cylinders. However, fuel pressure should be measured to ensure sufficient fuel supply.
• If there is no smoke from the exhaust during engine crank, fuel may not be getting to the engine cylinders.
See “Priming the Fuel System” in Section 4 (page 132) for procedure.
Possible Causes
Engine will not turn over
• Low or no battery power
• No key power (vIGN)
• Insufficient power to ECM
• Starting system failure
• Circuit fault for Engine Crank Inhibit (ECI)
• Cylinder hydraulic lock
• Cylinder mechanical lock (timing incorrect; valve/piston contact) Insufficient rpm
• Low battery power
• Starter motor problem
• Incorrect oil viscosity
• Cold temperature
Insufficient oil pressure
• Oil gauge error on instrument panel (will not cause hard start or no start)
• Low oil level: oil leak, oil consumption, or incorrect servicing
• High oil level: incorrect servicing, fuel in oil, coolant in oil
• Incorrect oil viscosity
• Stuck oil pressure regulator
• Scored or damaged oil pump/front cover
• Engine Oil Pressure (EOP) sensor biased
• Incorrect EOP sensor
• EOP circuit or sensor problems
• Broken, missing, or loose piston cooling tubes
• Missing, damaged, or worn bearing inserts
• Missing, damaged, or worn camshaft bushings
• Lifter missing (will also have performance problems) Excessive exhaust smoke with hard start or no start concern
• Poor fuel quality
• Insufficient cylinder temperature
• Loose injector
• Low compression
• Inoperable inlet air heater system – if equipped
• Excessive air inlet or exhaust restriction
• Damaged injector – split tip
• Base engine timing incorrect
• Combustion leak to fuel
No exhaust smoke / cylinders not receiving fuel
• Fuel supply system concern
• ECM and IDM communication failure
• ICP sensor bias high (above 3.45 MPa [500 psi])
• Combustion leak to fuel supply (fuel rail)
• Base engine timing incorrect
