Code 1 - O2 Sensor
- Turn ignition off. Remove BACK-UP light fuse in underhood fuse/relay block for 10 seconds to reset ECU. Start and warm engine to normal operating temperature (cooling fan comes on).
- Road test vehicle with transmission in 2nd gear. Accelerate at wide open throttle for at least 5 seconds and then decelerate for at least 5 seconds with throttle completely closed.
- If CHECK ENGINE light illuminates and Code 1 is present, perform test for Code 43. If CHECK ENGINE light does not illuminate and Code 1 is not present, problem is intermittent. Check for poor connections and loose wires at connector No. C210 (at right shock tower), and check O2 sensor connector.