Hard to Start

DEFINITION
Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies.

PRELIMINARY CHECKS
- Refer to Important Preliminary Checks. - Important Preliminary Checks
- Make sure the driver is using the correct starting procedure.
- Check fuel quality. Refer to Fuel Specific Gravity Check in Fuel System. Testing and Inspection
- Check engine oil level and quality.
- Remove air cleaner filter and check for being plugged, replace as necessary.

SENSORS
- CHECK: Engine Coolant Temperature (ECT) sensor Using a scan tool, compare engine coolant temperature with ambient temperature on a cold engine.
- If coolant temperature reading is 5° greater than or less than ambient air temperature on a cold engine, check for high resistance in coolant sensor circuit or sensor itself. Refer to DTC 15 and compare resistance values. Testing and Inspection

FUEL SYSTEM
- CHECK: Supply to injection pump. Refer to Fuel System. Fuel Supply Line
- CHECK: Fuel return from injection pump. Refer to Fuel System. Fuel Return Line
- CHECK: Engine shut-off solenoid operation. Refer to Diagnostic Trouble Code (DTC) Charts. Testing and Inspection
- CHECK: Fuel injection nozzles. Refer to Fuel System. Testing and Inspection
- CHECK: Fuel tank cap vent.
- CHECK: Internal injection pump problem.

ELECTRICAL SYSTEMS
- CHECK: Glow plug operation. Refer to Glow Plug System. Testing and Inspection
- CHECK: Slow cranking speed.

AIR INTAKE SYSTEMS
- CHECK: Air cleaner and air intake ducts for restriction.
- CHECK: Restriction in intake manifold.

EXHAUST SYSTEM
- CHECK: Exhaust system for possible restriction. Refer to Exhaust Systems.

ADDITIONAL CHECKS
- CHECK: No crank signal. Refer to DTC Charts. Testing and Inspection
- CHECK: Service Bulletins for PROM updates. PROM - Programmable Read Only Memory