Circuit/System Verification
- If there are other DTCs set besides DTC P2177, P2179, P2187, or P2189, refer to DIAGNOSTIC TROUBLE CODE (DTC) LIST - VEHICLE DIAGNOSTIC INFORMATION
to diagnosis the applicable DTC.
- Ignition ON, observe the barometric pressure (BARO) sensor pressure parameter and compare the reading on the scan tool to the barometric pressure table. Refer to ALTITUDE VERSUS BAROMETRIC PRESSURE .
- Engine at normal operating temperature, observe the Total Fuel Trim Avg. parameter with a scan tool. The Total Fuel Trim Avg. should be between -22 to +23 percent.