Circuit/System Verification
WARNING: This page is about a different car, the 2018 Chevrolet Suburban 3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- Engine - Running
- Verify there is no abnormal noise from the component: Engine
- If an abnormal noise is present
Refer to Symptoms - Engine Mechanical
- Go to next step: If no abnormal noise is present
- If an abnormal noise is present
- Perform the scan tool learn/reset function: Crankshaft Position Variation Learn
- 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
- If other DTCs are set
- Go to next step: If no other DTCs are set
- 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
- If the parameter value increments
- 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
- If the engine sound does not change the same way for one or more cylinders
- 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
- 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
- If the DTC sets
- All OK.