GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Alero Export 🢒 Engine 🢒 Engine Controls - 2.4L 🢒 Surges/Chuggles

Surges/Chuggles

Tests/inspections

Action

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 position.

Preliminary
    • Refer to Symptoms .
    • Search for service bulletins.
    • Be sure the customer understands the transmission torque converter clutch, and the A/C compressor operation as explained in the owner's manual. Inform the customer how the TCC and the A/C clutch operate.
    • Verify that the PCM grounds are clean, tight, and in the correct locations.

Sensor/System
    • Oxygen sensor (O2S 1): The O2S 1 should respond quickly to different throttle positions. If not, inspect the O2S 1 for silicon or other contaminants from fuel or the use of improper RTV sealant. The sensor may have a white powdery coating. Silicon contamination causes a high but false O2S 1 signal voltage (rich exhaust indication). The PCM will reduce the amount of fuel delivered to the engine, causing a severe driveability problem. Refer to Information Sensors/Switches Description .
    • Test for correct operation of the manifold absolute pressure (MAP) sensor. Refer to Manifold Absolute Pressure Sensor Output Diagnosis .
    • Test for the correct operation of the throttle position (TP) sensor.
    • Test for the correct operation of the engine coolant temperature (ECT) sensor.

Fuel System
    • Test for the correct fuel pressure. Refer to Fuel System Diagnosis .
    • Test for contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Inspect the fuel filter for restrictions.
    • Ensure that each fuel injector harness is connected to the correct fuel injector. Refer to Engine Controls Schematics .
    • Check any items which can cause an engine to run rich (long term fuel trim is significantly in the negative range). Refer to Diagnostic Aids for DTC P0172 Fuel Trim System Rich .
    • Check any items that can cause an engine to run lean (long term fuel trim is significantly in the positive range). Refer to Diagnostic Aids for DTC P0171 Fuel Trim System Lean .

Ignition System
    • Test for the correct ignition voltage output.
    • Inspect the spark plugs for the following conditions:
       - Any moisture or fuel fouling
       - Any cracks
       - An incorrect gap
       - Any burnt electrodes or heavy deposits
    • If the spark plugs are fuel or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.
    • Inspect the ignition control module (ICM) for a correct ground connection.
    • Inspect the ignition coils for cracks or carbon tracking.

Additional
    • Test for correct operation of the TCC. Refer to Road Test in Automatic Transaxle.
    • Inspect the exhaust system for following conditions:
       - Any damaged or collapsed pipes.
       - Any heat distress or internal failure of the muffler.
       - A plugged 3-way catalytic converter. Refer to Restricted Exhaust System Check .
    • Inspect the vacuum lines for kinks or leaks.
    • Test the generator output voltage. Refer to Diagnostic System Check - Engine Electrical in Engine Electrical.

If all procedures have been completed and no malfunctions have not been found, test and inspect all the connections within the suspected circuit and system.

Observe the scan tool data for the suspected circuit and/or systems.