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 block learn values on Scan tool for system running lean (short term near 147).
^ Monitor block lean values on Scan tool for system running rich (short term FT near 101).

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