Specifications

DIAGNOSIS AND TESTING
ENGINE DIAGNOSIS—PERFORMANCE
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL NOT CRANK OR
CRANKS SLOWLY
1. Starting motor operating, but not cranking
the engine.
1. Remove the starter motor. Check for broken
flywheel teeth or a broken starter motor spring.
2. Crankshaft rotation restricted. 2. Rotate the engine to check for rotational
resistance.
3. Starting circuit connections loose or
corroded.
3. Clean and tighten connections.
4. Neutral safety or starter relay inoperative. 4. Check starter relay supply voltage and
proper operation of neutral safety switch (if
equipped). Replace defective parts.
5. Battery charge low. 5. Check Battery voltage. Replace battery if a
charge cannot be held.
6. No voltage to starter solenoid. 6. Check voltage to solenoid. If necessary,
replace the solenoid.
7. Solenoid or starter motor inoperative. 7. Replace starter motor.
ENGINE CRANKS, BUT WILL
NOT START, NO SMOKE
1. No fuel in supply tank. 1. Fill fuel supply.
2. Electrical fuel shutdown solenoid not
operating.
2. Check for loose wires and verify that the
fuel shutdown solenoid is functioning. Check
for fault codes in the ECU.
3. Fuel injection system defective: Cranking
speed sensor. Loose connection between
ECU and harness. No power supply to the
ECU. Loose connection between injection
pump and harness.
3. Check for fault codes at ECU. Refer to
Group 14, Fuel System for repairs procedures.
4. Air intake or exhaust plugged. 4. Remove the obstruction.
5. Fuel filter plugged. 5. Drain fuel/water separator and replace fuel
filter.
6. Excessive fuel inlet restriction. 6. Check for restriction. Correct cause.
7. Injection pump not getting fuel or fuel is
aerated.
7. Check fuel flow/bleed fuel system.
8. One or more injectors worn or not
operating properly.
8. Check/replace bad or improperly operating
injectors.
9. Camshaft out of time. 9. Check/correct timing chain sprocket
alignment.
ENGINE HARD TO START, OR
WILL NOT START, SMOKE FROM
EXHAUST
1. Incorrect starting procedure. 1. The fuel shutoff solenoid control must be in
the run position. Ensure the proper procedure
is being used.
2. Cranking speed to slow. 2. Check the battery, starter motor and look for
loose or corroded wiring connections.
3. Cylinder head heater plugs defective. 3. Verify system is working. Verify connection
between heater plug relay and ECU.
Repair/replace inoperative parts.
4. Insufficient intake air 4. Inspect or replace air filter and check for
obstruction in air supply.
5. Air in fuel system or the fuel supply is
inadequate.
5. Check the fuel flow through the filter and
bleed system. Locate and eliminate the air
source.
6. Contaminated fuel. 6. Verify by operating the engine with clean
fuel from a temporary tank. Check for the
presence of gasoline. Drain and flush fuel
supply tank. Replace fuel/water separator filter.
7. Fuel screen plugged. 7. Check fuel screen.
8. One or more injectors worn or not
operating properly.
8. Check/replace improperly operating
injectors.
9. Injector pump out of time. 9. Check pump timing. Refer to Group 14,
Fuel System for procedure.
10. Engine compression low. 10. Check compression to identify the
problem.
11. Fuel injection system defective. 11. Vacuum modulator defective causing EGR
to open in cold condition. Check for fault
codes in the ECU.
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