Chrysler Concorde 2004 Service Manual page 785

P0300-MULTIPLE CYLINDER MISFIRE —
TEST
1 Read and record the FREEZE FRAME DATA. Select OBD II MONITORS. Read and
record the MIS-FIRE SIMILAR CONDITIONS WINDOW DATA.
With these screens, attempt to duplicate the condition(s) that has set this DTC.
When the vehicle is operating in the SIMILAR CONDITIONS WINDOW, refer to the
WHICH CYLINDER IS MISFIRING screen.
Observe the WHICH CYLINDER IS MISFIRING screen for at least one minute.
Is there a misfire present?
Yes → Go To 2
No
2 NOTE: Reviewing the vehicle repair history may aid in the repair of the
misfire condition.
Visually and physically inspect the engine for any of the following conditions.
- Worn serpentine belt
- Binding Engine-Driven accessories.
- Misaligned water pump, P/S pump and A/C compressor pulleys
- Improper CKP sensor mounting
- Poor connector/terminal to component connection. i.e., CKP sensor, Fuel Injector,
Ign coil, etc.
- Vacuum leaks
- Restricted Air Induction system
NOTE: Read the CKP SYNC state on the DRB. If the CKP SYNC does not
indicate IN SYNC, perform the Crankshaft Position Sensor Circuit chart.
NOTE: Ensure the powers and grounds for the PCM are operating properly.
Were any of the above conditions present?
Yes → Repair as necessary.
No
3 Turn the ignition off.
Disconnect the Ignition Coil harness connector.
Remove the Ignition Coil.
NOTE Before continuing, inspect the Ignition Coil for the following condi-
tions. If a problem is found, replace the Ignition Coil. Damage or Carbon
Tracking on the Coil or the spark plug insulator boot.
Install a spark tester to the Ignition Coil.
Reconnect the Ignition Coil harness connector to the Ignition Coil.
While cranking the engine, observe the spark coming from the spark tester.
NOTE: A crisp blue spark should be generated that is able to jump the gap
of the spark tester.
Is good spark present?
Yes → Go To 4
No
ACTION
→ Go To 17
Perform POWERTRAIN VERIFICATION TEST VER - 5 - NGC.
→ Go To 3
→ Go To 14
DRIVEABILITY - NGC
Continued
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APPLICABILITY
All
All
All