October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.

Confirm Part Inspection

Does the HO2S upstream (S1) operate properly? (Check variation)
YES
- Go to "Verification of Vehicle Repair " procedure.
NO
- Carefully re-do this troubleshooting guide steps.
- If problem still occurs, replace HO2S upstream (S1) and then go to "System Inspection" procedure.