GM Service Manual Online
For 1990-2009 cars only

Surges/Chuggles EFI

Checks

Action

Definition: The engine has a power variation under a steady throttle or cruise. The vehicle feels as if it speeds up and slows down with no change in the accelerator pedal.

Preliminary Checks

    • Refer to Symptoms .
    • Be sure the driver understands the Torque Converter Clutch (TCC) operation.
    • Be sure the driver understands the A/C compressor operation.

Fuel System Checks

Check the fuel pressure while the condition exists. Refer to Fuel Supply System Check .

Additional Checks

    • Check the control module grounds for being clean, tight, and in their proper locations.
    • Check the vacuum lines for kinks or leaks.

Surges/Chuggles MFI

Checks

Action

Definition: The engine has a power variation under a steady throttle or cruise. The vehicle feels as if it speeds up and slows down with no change in the accelerator pedal.

Preliminary Checks

    • Refer to Symptoms .
    • Be sure the driver understands the Torque Converter Clutch (TCC) operation.
    • Be sure the driver understands the A/C compressor operation.

Fuel System Checks

Check the fuel pressure while the condition exists. Refer to Fuel Supply System Check .

Additional Checks

    • Check the control module grounds for being clean, tight, and in their proper locations.
    • Check the generator output voltage. Repair if less than 9 or more than 16 volts.
    • Check the vacuum lines for kinks or leaks.
    • Check the TCC operation.