Surges/Chuggles

DEFINITION
Engine power variation, under steady throttle or cruise. Feels like the vehicle speeds up and slows down, with no change in the accelerator pedal.

PRELIMINARY CHECKS
^ Refer to "Important Preliminary Checks." Testing and Inspection
^ Be sure driver understands Torque Converter Clutch (TCC) and A/C compressor operation in owners manual.
^ Use a scan tool to make sure reading of Vehicle Speed Sensor (VSS) matches vehicle speedometer except vehicles with electronic transmissions where some variation between VSS and speedometer is normal. FUEL SYSTEM
^ CHECK: Fuel pressure while condition exists.

ADDITIONAL CHECKS
^ CHECK: Control module grounds for being clean, tight, and in their proper locations.
^ CHECK: Generator output voltage. Repair if less than 9 or more than 16 volts.
^ CHECK: Vacuum lines for kinks or leaks.
^ CHECK: For intermittent EGR.
^ CHECK: TCC operation.