Diagnostic Procedures
WARNING: This page is about a different car, the 1997 GMC Pickup and 1997 Chevrolet Pickup. However, it is still accessible from the selected car via links, so may be relevant.
- Perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK. See the F - BASIC TESTING - 4.3L article. After performing OBD system check, go to next step.
- Install scan tool. Start and run engine for greater than 2 minutes. Ensure engine is operating at normal operating temperature. Using scan tool, command AIR pump on. If bank 1 short term fuel trim indicates a change of greater than 6 percent, go to next step. If bank 1 short term fuel trim does not indicate a change of greater than 6 percent, go to step 4).
- DTC is intermittent. If no additional DTCs are set, see DIAGNOSTIC AIDS. If any additional DTCs are set, go to applicable DTC test.
- Disconnect bank 1 AIR crossover hose from AIR valve. Using scan tool, command AIR pump on. Observe if air flows from AIR valve. If air flows from valve, go to next step. If air does not flow from valve, go to step 7).
- Check for restrictions or leaks in bank 1 AIR pipe, hoses and fittings. If a problem was found, go to next step. If a problem was not found, go to step 2).
- Repair as necessary. After repairs, go to next step.
- Using scan tool, select DTC, CLEAR INFO. Start and warm engine to normal operating temperature. Select DTC, SPECIFIC, then enter DTC P1415. Operate vehicle within the conditions for setting this DTC. If scan tool indicates that this test ran and passed, go to next step. If scan tool does not indicate that this test ran and passed, repeat step 2).
- Using scan tool, select CAPTURE INFO, REVIEW INFO. If any undiagnosed DTC(s) are displayed, go to applicable DTC test.