GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Tracker - 4WD 🢒 Engine 🢒 Engine Controls - 1.6L 🢒 Surges/Chuggles

Surges and/or Chuggles

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 A/C compressor operation.
    • Use a scan tool to make sure the reading of VSS matches vehicle speedometer. This excludes vehicles with electronic transmissions where some variation between VSS and the speedometer is normal.

Sensor Check
    • Check the performance of the MAF sensor. Refer to Diagnostic Aids in DTC P0101 Mass Air Flow (MAF) Sensor Performance .
    • Inspect the operation of the heated oxygen sensor (HO2S) 1. Refer to:
    • Inspect for a shifted or fixed engine coolant temperature (ECT) sensor. Test the ECT sensor using the scan tool. Compare the engine coolant temperature with the ambient air temperature on a cold engine. If the engine coolant temperature is more than 5°C (9°F) more or less than the ambient air temperature, check for a high resistance in the coolant sensor circuit or the sensor itself. Refer to Temperature Versus Resistance .

Fuel System Checks
    • Check if a Rich or Lean system can cause the condition. Drive the vehicle at the speed of the complaint. Monitoring the Fuel Trim may help identify the problem.
       - Lean - The Long Term Fuel Trim will be more than 20 percent. Refer to DTC P0171 Fuel Trim System Lean Diagnostic Aids.
       - Rich - The Long Term Fuel Trim will be less than -20 percent. Refer to DTC P0172 Fuel Trim System Rich Diagnostic Aids.
    • Check the fuel injectors. Perform the Fuel Injector Coil Test Procedure and the Fuel Injector Balance Test Procedure. Refer to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F) and Fuel Injector Balance Test .
    • Check the fuel pressure while the condition exists. Refer to Fuel System Diagnosis .

Ignition System Checks
    • Check for the proper secondary voltage output with a J 26792 spark tester, or equivalent.
    • Check the spark plugs for any of the following conditions:
       - Wet (fuel fouled) spark plugs
       - A terminal screw that is bent or loose (rotate and pull)
       - A ceramic insulator that has cracks, carbon tracking, or deposits (red or black dust)
       - A tip insulator that has cracks, carbon tracking, deposits (oil, carbon, glazing, fuel additive), or is loose (rattles)
       - A center electrode that is loose (wiggles side to side)
       - An incorrect spark plug gap that is too large or too small
       - Platinum pads that are missing

Additional Checks
    • Check the generator output voltage.
    • Check the vacuum lines and hoses for kinks or leaks. Review the Vehicle Emission Control Information label.
    • Check for an intermittent EGR problem.