By-Pass Air Control (BAC) Valve
- Remove BAC valve from throttle body. See Fig 1 . Blow air through port "A". Ensure air exhausts through port "B" when valve is cold. If not, replace BAC valve.
- Measure resistance of Idle Speed Control (ISC) valve at 2 wire connector of BAC valve. Resistance should be between 6.3-9.9 ohms, at normal operating temperature. If not, replace BAC valve.