Circuit/System Verification
WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition - On / Vehicle - In Service Mode
- Verify DTC P0641, P0651, P0697, P06A3, P06D2 is not set.
- If any of the DTCs are set
- Go to next step: If none of the DTCs are set
- Verify the scan tool parameter:Throttle Body Idle Air Flow Compensation = Less than 90%
- If 90% or greater
- Go to next step: If less than 90%
- Perform the scan tool control function:Throttle Sweep - On
Verify the scan tool parameter: Throttle Position Sensors 1 and 2 = Agree
- If not the specified state
Refer to:DTC P0121-P0123, P0222, P0223, P16A0-P16A2, or P2135
- Go to next step: If the specified state
- If not the specified state
- Determine the current vehicle testing altitude.
- Verify the scan tool parameter:
- Boost Pressure Sensor = Altitude Versus Barometric Pressure - The value should be within the range listed in the table.
- MAP Sensor = Altitude Versus Barometric Pressure - The value should be within the range listed in the table.
- If not in the specified range
- Go to next step: If in the specified range
- Verify the following conditions do not exist:
- Vacuum leak at the component:
- Intake Manifold
- B65 Intake Manifold Pressure and Air Temperature Sensor
- B111 Turbocharger Boost Sensor
- Q38 Throttle Body
- An object is blocking the component:
- Q38 Throttle Body
- Intake Air Duct
- Loose clamps, cracks, or other damages to the intake system.
- Water intrusion at the mass air flow sensor.
- Contamination of the measuring element of the mass air flow sensor.
- Missing, restricted or leaking exhaust components. Refer to:Symptoms - Engine Exhaust
- An engine mechanical condition. Refer to:Symptoms - Engine Mechanical
- If a condition exists
Repair or replace the components as necessary.
- Go to next step: If no condition exists
- Vacuum leak at the component:
- Engine idling.
- Verify the scan tool parameter: Boost Pressure Sensor = The value should change with accelerator pedal input.
- If the value does not change
Refer to:DTC P0236
- Go to next step: If the value changes
- If the value does not change
- Verify the scan tool parameter:MAP Sensor = 26 to 52 kPa (3.8 to 7.5 PSI) and changes - The value should change with accelerator pedal input.
- If not between 26 and 52 kPa (3.8 and 7.5 PSI) or does not change
Refer to:DTC P0106
- Go to next step: If between 26 and 52 kPa (3.8 and 7.5 PSI) and changes
- If not between 26 and 52 kPa (3.8 and 7.5 PSI) or does not change
- Monitor the scan tool parameter: MAF Sensor
Perform the following steps:
- Perform the scan tool snapshot function.
- Increase the engine speed slowly to 3, 000 RPM and then back to idle.
- Exit the Snapshot function.
- While reviewing the data frame by frame, the parameter should change smoothly and gradually as the engine speed was increased and decreased.
- If the value does not change smoothly and gradually
Refer to:DTC P0101
- Go to next step: If the value changes smoothly and gradually
- 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 that no DTCs are set.
- If any DTC is set
- Go to next step: If no DTC is set
- All OK.
NOTE:
While reviewing the data frame by frame, the parameter should change smoothly and gradually as the engine speed was increased and decreased.