2006 GMC ENVOY Fuel lines

If the water is not too deep, drive slowly through it. At
faster speeds, water splashes on the ignition system and
your vehicle can stall. Stalling can also occur if you
get the tailpipe under water. And, as long as the tailpipe
is under water, you will never be able to start the
engine. When you go through water, remember that
when the brakes get wet, it may take you longer to stop.
{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your
vehicle downstream and you and your
passengers could drown. If it is only shallow
water, it can still wash away the ground from
under your tires, and you could lose traction
and roll the vehicle over. Do not drive through
rushing water.
SeeDriving in Rain and on Wet Roads on page 4-33for
more information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis, or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires, and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
4-31

Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This may cause wind
noise and affect windshield washer performance. Check
with your dealer before adding equipment to the
outside of your vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you may 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, your
engine needs service.
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 5-6
for additional information.
5-5

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 3-42. 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.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area. General Motors recommends that you use
these gasolines if they comply with the specications
described earlier. However, E85 (85% ethanol)
and other fuels containing more than 10% ethanol must
not be used in vehicles that were not designed for
those fuels.
5-6

Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors
recommends against the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs
and the performance of the emission control system may
be affected. The malfunction indicator lamp may turn
on. If this occurs, return to your authorized GM dealer
for service.Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-7

Sheet Metal Damage
If the vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti-corrosion material to parts repaired or
replaced to restore corrosion protection.
Original manufacturer replacement parts will provide the
corrosion protection while maintaining the warranty.
Finish Damage
Any stone chips, fractures or deep scratches in the
nish should be repaired right away. Bare metal
will corrode quickly and may develop into major
repair expense.
Minor chips and scratches can be repaired with
touch-up materials available from your GM dealer.
Larger areas of nish damage can be corrected in
your GM dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, corrosion and rust can develop on the
underbody parts such as fuel lines, frame, oor
pan, and exhaust system even though they have
corrosion protection.
At least every spring, ush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of
the frame should be loosened before being ushed.
Your dealer or an underbody car washing system can
do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces on the vehicle. This damage can
take two forms: blotchy, ring-shaped discolorations,
and small, irregular dark spots etched into the
paint surface.
Although no defect in the paint job causes this, GM will
repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs rst.
5-99