gas type GMC YUKON DENALI 2007 Owners Manual

Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 424for 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 may be affected. The malfunction
indicator lamp may turn on and your vehicle
may fail a smog-check test.SeeMalfunction Indicator Lamp on page 237.
If this occurs, return to your authorized GM dealer
for diagnosis. If it is determined that the condition
is caused by the type of fuel used, repairs
may not be covered by your warranty.
Additives
To provide cleaner air, all gasolines in the
United States are now required to contain additives
that will help prevent engine and fuel system
deposits from forming, allowing your emission
control system to work properly. In most cases,
you should not have to add anything to your fuel.
However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations.
To help keep fuel injectors and intake valves clean,
or if your vehicle experiences problems due to
dirty injectors or valves, look for gasoline that is
advertised as TOP TIER Detergent Gasoline.
Also, your GM dealer has additives that will help
correct and prevent most deposit-related problems.
424

{CAUTION:
If you spill fuel and then something ignites
it, you could be badly burned. Fuel can
spray out on you if you open the fuel cap
too quickly. 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 530.
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 237.If your vehicle has a Driver Information Center
(DIC), the TIGHTEN GAS CAP message will be
displayed if the fuel cap is not properly installed.
{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 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. See
Malfunction Indicator Lamp on page 237.
427

Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 478.
For any bulb changing procedure not listed in
this section, contact your dealer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas
inside and can burst if you drop or
scratch the bulb. You or others could be
injured. Be sure to read and follow the
instructions on the bulb package.
Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
A. Stoplamp/Taillamp
B. Turn Signal/Taillamp
C. Back-up Lamp
476