Preliminary Checks

The following should be checked prior to diagnosing the fuel system:

• Inspect ignition cables and routing. Ensure spark exists at spark plugs.
• Ensure all electrical connectors are secured on all sensors and switches.
• Verify all hoses and connections are tight and in good condition.
• Check alternator wiring and connections.
• Ensure engine ground strap is connected at the engine and dash panel.
• Ensure EGR valve tube-to-intake plenum is secure.
• Ensure pin connectors at SMEC are secure.

If the "CHECK ENGINE" light comes on, or if certain driveability or engine performance difficulties exist, the probable source of these difficulties may be determined by entering "On-Board Diagnostics" and recording the trouble codes as they are displayed. Trouble codes may be displayed on the Chrysler Motors Diagnostic Readout Box (C-4805) or, to a limited extent, be flashed on the "CHECK ENGINE" light.

The SMEC contains test modes. Corresponding codes are used for each diagnostic mode. All test modes must be used to properly diagnose the system. For further information, see CHRYSLER MOTORS 3.0L ENGINE CONTROL SYSTEM in the COMPUTERIZED ENGINE CONTROLS section.