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Home >> Chevrolet >> 2018 >> Suburban 3500 HD LT >> Repair and Diagnosis >> External Pages >> Different car >> Section 2 (Engine Controls And Fuel - 5.3L (L83) Or 6.2L (L86) - DTC P0010 To DTC P0442) >> Diagnostic Information And Procedures >> DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308: Misfire Detected >> Circuit/System Verification

Circuit/System Verification

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban, and 2018 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.
  1. Engine - Running
  2. Verify there is no abnormal noise from the component : Engine
    • Go to next step : If no abnormal noise is present 
  3. Perform the scan tool learn/reset function : Crankshaft Position Variation Learn
  4. Verify there are no DTCs set related to the following system/component :
    • B23 Camshaft Position Sensor
    • B26 Crankshaft Position Sensor
    • B52 Heated Oxygen Sensor
    • Fuel System
    • Ignition System
    • Mechanical Condition
    • Go to next step : If no other DTCs are set 
  5. Verify the scan tool parameter : Cylinder 1-8 Current Misfire Counter = Does not Increment.
    • If the parameter value increments 

      Refer to Circuit/System Testing below

    • Go to next step : If the parameter value does not increment 
  6. Perform the scan tool control function : Cylinder Power Balance - Enable

    Verify the sound of the engine changes the same way when turning off each individual injector.

    • If the engine sound does not change the same way for one or more cylinders 

      Refer to Circuit/System Testing below

    • Go to next step : If the engine sound changes the same way for all cylinders 
  7. Verify the scan tool parameter : Cylinder 1-8 Current Misfire Counter = Does not Increment.

    Perform the action while monitoring the parameter :

    • Wiggle the harness and connector : K20 Engine Control Module
    • Wiggle the harness and connector : Q17 Fuel Injector
    • Wiggle the harness and connector : T8 Ignition Coil
    • Wiggle the component : Vacuum Hoses
    • If the parameter value increments 

      Repair or replace as necessary.

    • Go to next step : If the parameter value does not increment 
  8. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

    Verify the DTC does not set.

    • If the DTC sets 

      Refer to Circuit/System Testing below

    • Go to next step : If the DTC does not set 
  9. All OK.
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