Surges/Chuggles

DEFINITION: Engine power variation under steady throttle or cruise. Feels like vehicle speeds up and slows down with no change in throttle position.
^ Check misfire counts using Scan tool (if any exist).
^ Verify proper TCC operation and customer understanding of TCC.
^ Verify proper A/C clutch operation.
^ Monitor short term fuel trim values on Scan tool to check whether system is running rich or lean.

Check:
^ EGR Operation.
^ Generator output voltage.
^ Vacuum lines for kinks or leaks.
^ Fuel pressure.
^ Spark plugs for cracks, wear, burned or heavy deposits on electrodes.
^ Fuel quality.