Circuit/System Verification
IMPORTANT:
Verify that the engine is in good mechanical condition before continuing with this diagnostic.
- If DTCs P0698 or P0699 are set, diagnose those codes first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- With the ignition ON, use a scan tool to observe the MAP and BARO parameters. Verify the MAP and BARO sensor parameters are within 5 kPa of each other.
- With the engine running, slowly increase the engine speed from idle to 2,000 RPM, then allow the engine speed to return idle. The MAP sensor parameter should increment to a higher value at 2,000 RPM and return near BARO at idle speed.
- Verify the integrity of the air induction system by inspecting for the following conditions:
- Damaged components
- Loose or improper installation
- An air flow restriction
- Verify that any electrical aftermarket devices are properly connected and grounded. Refer to Checking Aftermarket Accessories .
IMPORTANT:
If you cannot duplicate the condition, 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.