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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 Wave 🢒 Engine 🢒 Engine Controls - 1.6L (L91) 🢒 Detonation/Spark Knock

Detonation/Spark Knock

Checks

Action

DEFINITION: A mild to severe ping which usually occurs worse while under acceleration. The engine makes sharp metallic knocks that change with throttle opening.

Preliminary Checks
    • Refer to Important Preliminary Checks Before Starting in Symptoms - Engine Controls .
    • Search for bulletins.
    • Verify that the engine control module (ECM) grounds are clean, tight, and in the correct locations.
    • If the scan tool readings are normal and there are no engine mechanical conditions, fill the fuel tank with a known high quality fuel that meets the vehicle's minimum octane requirements. Refer to Symptoms - Engine Controls . Road test the vehicle and re-evaluate the vehicle's performance.

Fuel System
    • Test for incorrect fuel pressure. Refer to Fuel System Diagnosis .
    • Test for a contaminated fuel condition. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Test the fuel injectors. Refer to Fuel Injector Solenoid Coil Test .
    • Test or inspect items that can cause an engine to run lean. For a lean condition, refer to DTC P0171 .

Sensor/System

Use a scan tool to monitor the knock sensor (KS) system. Refer to Knock Sensor (KS) System Description and DTC P0327 .

Ignition System

Verify that the spark plugs are of the correct heat range. Refer to Ignition System Specifications .

Engine Cooling System

Test for obvious overheating conditions. Test or inspect for the following conditions:

    • Low engine coolant level
    • Incorrect engine coolant
    • Restricted air flow to the radiator or restricted coolant flow through the radiator
    • Engine coolant leaks
    • Incorrect fan operation
        Refer to the following procedures in Engine Cooling:
       -  Engine Overheating
       -  Symptoms - Engine Cooling

Engine Mechanical

Inspect for the following engine mechanical conditions:

    • Excessive oil in the combustion chambers and for leaking valve seals.
    • High cylinder compression. Refer to Engine Compression Test in Engine Mechanical - 1.6L (L91).
    • Excessive carbon buildup in the combustion chambers. Clean the chambers with top engine cleaner. Follow the instructions on the can.
    • Inspect the following for incorrect basic engine parts:
       - The camshaft
       - The cylinder heads
       - The pistons, connecting rods, and bearings
       - Refer to the following procedures in Engine Mechanical - 1.6L (L91):

Additional Checks

Test the transmission torque converter clutch (TCC). Applying the TCC too soon can cause the engine to spark knock. Refer to Symptoms - Automatic Transmission in Automatic Transmission - Aisin (81-40LE).