Diagnostic Aids

The system is designed for use of regular unleaded fuel to any ethanol concentration up to 85 percent (E85). When the ambient temperature drops below minus 14°F (10°C), a winter blend of 70 percent (E70), or less is recommended for cold weather starting. If the ethanol concentration is higher (E85), a DTC P0169 will set. Adding regular unleaded fuel to bring the alcohol content lower is recommended. Cold start cranking time should improve. This system is not designed for methanol fuel. Use of methanol fuel will cause the fuel composition sensor to read a higher percentage than that which exists and could cause a DTC P0169 to set, with a DTC P0179 also possible if the concentration is high enough (M85). The wrong fuel (M85) will also cause damage to the fuel system components and should be drained from the tank if found. Other contamination of alcohol blended fuels include water and salts. These compounds, if contained in the fuel, will also cause a higher than expected alcohol content reading causing a DTC P0169 to set. The table below shows the maximum thresholds of a given ethanol content, or percentage, versus the ambient temperature at which a DTC P0169 will set. See ETHANOL PERCENTAGE VS AMBIENT TEMPERATURE  table.