Fuel E85 (85% Ethanol) - Chevrolet 2010 Impala Owner's Manual

Fuel E85 (85% Ethanol)

The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies the
vehicle's engine. The VIN is at the top left of the
instrument panel. See Vehicle Identification Number
(VIN) on page 6-95.
If the vehicle has the 3.5L V6 engine (VIN Code K)
or the 3.9L V6 engine (VIN Code M), you can use either
unleaded gasoline or ethanol fuel containing up to
85% ethanol (E85). See Fuel on page 6-5. In all other
engines, use only the unleaded gasoline described
under Gasoline Octane on page 6-6.
Only vehicles that have the 3.5L V6 engine (VIN Code K)
or the 3.9L V6 engine (VIN Code M) can use 85% ethanol
fuel (E85). We encourage the use of E85 in vehicles
that are designed to use it. The ethanol in E85 is a
"renewable" fuel, meaning it is made from renewable
sources such as corn and other crops.
Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U.S. Department
of Energy has an alternative fuels website
(www.eere.energy.gov/afdc/infrastructure/locator.html)
that can help you find E85 fuel. Those stations that
do have E85 should have a label indicating ethanol
content. Do not use the fuel if the ethanol content
is greater than 85%.
6-8
At a minimum, E85 should meet ASTM Specification
D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specifications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according to
ASTM specification D 5798. If you have trouble starting
on E85, it could be because the E85 fuel is not properly
formulated for your climate. If this happens, switching to
gasoline or adding gasoline to the fuel tank can improve
starting. For good starting and heater efficiency below
32°F (0°C), the fuel mix in the fuel tank should contain
no more than 70% ethanol. It is best not to alternate
repeatedly between gasoline and E85. If you do switch
fuels, it is recommended that you add as much fuel as
possible — do not add less than three gallons (11 L)
when refueling. You should drive the vehicle immediately
after refueling for at least seven miles (11 km) to allow the
vehicle to adapt to the change in ethanol concentration.