Display 8

Value less than 128 indicates mixture is too rich, and oxygen sensor control attempts to lean the mixture. Value greater than 128 indicates mixture is too lean, and oxygen sensor control attempts to richen the mixture. Ensure PCV hoses are disconnected from valve covers and hose ends are plugged. Wait 30 seconds to allow display to stabilize. Adjust idle mixture until value is 128. See IDLE SPEED & MIXTURE in the ADJUSTMENTS article. If value will not stabilize at 128, check for faulty oxygen sensor or oxygen sensor heater.