Inspection/Test
| Action
|
DEFINITION: Engine
cranks OK, but does not start for a long time. Does eventually run, or may
start but immediately dies.
|
Preliminary
|
|
Sensor/System
|
| • | Test the engine coolant temperature (ECT) sensor for being shifted
in value. Connect a scan tool and compare ECT with intake
air temperature (IAT) on a cold engine. The ECT and IAT should be
within ± 3°C (5°F) of each other. Test the
resistance of the ECT sensor if the temperature is out of
range with the IAT sensor. Refer to the
Temperature Versus Resistance
Table. If the ECT sensor resistance
is not within the specification, refer to
DTC P0117
or
DTC P0113
. |
| • | Monitor the 24 X crankshaft position (CKP) and camshaft
position (CMP) sensors on a scan tool. If both are not responding, test the
sensor feed circuit. Both sensors use a separate feed circuit but are
internally connected to power. Test all 24 X and CMP sensor circuits
for intermittents. Refer to
Testing for Intermittent Conditions and Poor Connections
in Wiring Systems. |
| • | Monitor the 3 X parameter on the scan tool. If the 3 X
is not responding, inspect the 7 X CKP sensor and circuits for intermittents.
Inspect the ignition control (IC) circuit, bypass circuit, 3 X reference
high circuit, and the 3 X reference low circuit for intermittents.
If these circuits become open or shorted, the conditions may not set a DTC
immediately, but are capable of causing driveability complaints. Refer
to
Testing for Intermittent Conditions and Poor Connections
in Wiring Systems. |
| • | Inspect the mass air flow (MAF) sensor for proper installation
and conditions. A MAF sensor with a damaged honeycomb may cause a hard start. |
| | Inspect the air intake ducts for being collapsed, damaged areas, looseness,
improper installation, or leaking, especially between the MAF sensor and
the throttle body. |
| • | Using a scan tool, test IAC operation. Command the engine RPM
to 1500 and back to the starting RPM. |
| | If the engine RPM does not change when commanded refer to
DTC P0506
and
DTC P0507
to diagnose the IAC System. |
|
Fuel
System
|
|
Ignition
System
|
| • | Inspect for proper ignition voltage output using the following
steps: |
| 1. | Attach the J 26792
Spark Tester to engine ground. |
| 2. | Connect the spark plug end of the spark plug wire to the J 26792
. Connect the other end
of the spark plug wire to the coil being tested. |
| 3. | Connect the spark plug end of the companion spark plug wire to
ground. |
The companion spark plug wire is the wire attached to the corresponding
coil tower.
| 4. | Crank the engine while observing the J 26792
. A spark should be observed. |
| 5. | Repeat the above steps for each coil. |
| • | If spark is not present at the coils, inspect for the following
conditions: |
| - | Coils--Cracks, carbon tracking/arcing, or a resistance value
outside the specified range. |
Coil Resistance
5000-8000 ohms (5K-8K ohms) | - | Spark Plug wires--Signs of arcing, cross firing, cracks,
carbon tracking, plug boot damage, pinched, improper routing, or a resistance
value outside the specified range. |
Spark Plug Wire Resistance
3000ohms per foot (9840ohms per meter).
| | Important: : Spraying the secondary ignition wires with a light mist of water may
help locate an intermittent condition. Ignition voltage will arc to ground
when a secondary component is faulty.
|
| - | Defective ignition module. |
| - | Ignition system wiring--Loose ignition module feed or ground
connection, or damaged system wiring. |
| • | Remove spark plugs and inspect for the following conditions: |
| - | Burned or damaged electrodes |
| - | Improper heat range or reach |
| • | If the spark plugs are gas or oil fouled, the cause of the fouling
must be determined before replacing the spark plugs. Refer to
Spark Plug Inspection
. |
|
Engine Mechanical
| Inspect the engine
for the following conditions:
| • | Excess oil in the combustion chamber. Inspect for leaking valve
seals. Refer to
Oil Consumption Diagnosis
in
Engine Mechanical. |
| • | Inspect for incorrect engine parts, such as the following basic
components: |
| - | Camshaft and valve train components |
|
