fuel type CHEVROLET IMPALA 2008 9.G Owners Manual

Gasoline Octane
For all vehicles except those with the 5.3L V8 engine
(VIN Code C), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you might notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated
at 87 octane or higher as soon as possible. If you are
using gasoline rated at 87 octane or higher and you hear
heavy knocking, the engine needs service.
If your vehicle has the 5.3L V8 engine (VIN Code C),
use premium unleaded gasoline with a posted
octane rating of 91 or higher. You can also use regular
unleaded gasoline rated at 87 octane or higher, but
your vehicle’s acceleration could be slightly reduced,
and you might notice a slight audible knocking
noise, commonly referred to as spark knock. If the
octane is less than 87, you might notice a heavy
knocking noise when you drive. If this occurs, use a
gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you could damage the engine.
If you are using gasoline rated at 87 octane or higher
and you hear heavy knocking, the engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM
Specication D 4814 in the United States or
CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines
containing MMT. SeeAdditives on page 5-7for
additional information.
California Fuel
If your vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specications. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance might be affected. The malfunction
indicator lamp could turn on and your vehicle might fail
a smog-check test. SeeMalfunction Indicator Lamp
on page 3-39. If this occurs, return to your authorized
dealer/retailer for diagnosis. If it is determined that
the condition is caused by the type of fuel used, repairs
might not be covered by your warranty.
5-6

{CAUTION:
Fuel can spray out on you if you open the fuel
cap too quickly. If you spill fuel and then
something ignites it, you could be badly burned.
This spray can happen if your tank is nearly full,
and is more likely in hot weather. Open the fuel
cap slowly and wait for any hiss noise to stop.
Then unscrew the cap all the way.
Be careful not to spill fuel. Do not top off or overll the
tank and wait a few seconds after you have nished
pumping before removing the nozzle. Clean fuel
from painted surfaces as soon as possible.
SeeWashing Your Vehicle on page 5-93.
When replacing the fuel cap, turn it clockwise
until it clicks. Make sure the cap is fully installed.
The diagnostic system can determine if the fuel cap has
been left off or improperly installed. This would allow
fuel to evaporate into the atmosphere. SeeMalfunction
Indicator Lamp on page 3-39.The TIGHTEN GAS CAP message will be displayed on
the Driver Information Center (DIC) if the fuel cap is
not properly installed. SeeDIC Warnings and Messages
on page 3-52for more information.
{CAUTION:
If a re starts while you are refueling, do not
remove the nozzle. Shut off the ow of fuel by
shutting off the pump or by notifying the
station attendant. Leave the area immediately.
Notice:If you need a new fuel cap, be sure to get
the right type. Your dealer/retailer can get one
for you. If you get the wrong type, it may not t
properly. This may cause your malfunction indicator
lamp to light and may damage your fuel tank and
emissions system. SeeMalfunction Indicator Lamp
on page 3-39.
5-11