2007 GMC ENVOY engine

Vehicle Identication.................................. 491
Vehicle Identication Number (VIN)........... 491
Service Parts Identication Label............... 491
Electrical System........................................ 492
Add-On Electrical Equipment..................... 492
Headlamps................................................ 492
Windshield Wiper Fuses............................ 492Power Windows and Other Power
Options.................................................. 492
Fuses and Circuit Breakers....................... 493
Engine Compartment Fuse Block............... 493
Rear Underseat Fuse Block....................... 499
Capacities and Specications.................... 502
Section 5 Service and Appearance Care
379

California Proposition 65 Warning
Most motor vehicles, including this one, contain
and/or emit chemicals known to the State of
California to cause cancer and birth defects or
other reproductive harm. Engine exhaust,
many parts and systems (including some inside
the vehicle), many uids, and some component
wear by-products contain and/or emit these
chemicals.
Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could
be damaged if you try to do service work
on a vehicle without knowing enough
about it.
Be sure you have sufficient knowledge,
experience, the proper replacement
parts, and tools before you attempt any
vehicle maintenance task.
Be sure to use the proper nuts, bolts,
and other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
If you want to do some of your own service work,
you will want to use the proper service manual.
It tells you much more about how to service your
vehicle than this manual can. To order the
proper service manual, seeService Publications
Ordering Information on page 545.
381

Your vehicle has an airbag system. Before
attempting to do your own service work, see
Servicing Your Airbag-Equipped Vehicle on
page 88.
You should keep a record with all parts receipts
and list the mileage and the date of any service
work you perform. SeeMaintenance Record
on page 521.
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. To
help keep your engine clean and maintain optimum
vehicle performance, GM recommends the use
of gasoline advertised as TOP TIER Detergent
Gasoline.
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.
382

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 383for 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 210. 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.
383

Filling the Tank
{CAUTION:
Fuel vapor burns violently and a fuel re
can cause bad injuries. To help avoid
injuries to you and others, read and follow
all the instructions on the pump island.
Turn off your engine when you are
refueling. Do not smoke if you are near
fuel or refueling your vehicle. Keep
sparks, ames, and smoking materials
away from fuel. Do not leave the fuel
pump unattended when refueling your
vehicle. This is against the law in some
places. Keep children away from the fuel
pump; never let children pump fuel.The tethered fuel cap is located behind a hinged
fuel door on the driver’s side of the vehicle.
To remove the fuel cap, turn it slowly
counterclockwise.
While refueling, hang the tethered fuel cap from
the hook on the fuel door.
385

Checking Things Under
the Hood
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, and
plastic or rubber. You or others could be
burned. Be careful not to drop or spill
things that will burn onto a hot engine.
Hood Release
1. To open the hood,
rst pull the handle
with this symbol
on it. It is located
inside the vehicle
under the instrument
panel on the
driver’s side.
388

Engine Compartment Overview
When you open the hood on the 4.2L L6 engine, here is what you will see:
390

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 400.
B. Engine Coolant Recovery Tank. SeeCooling
System on page 411.
C. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 418.
D. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 417.
E. Automatic Transmission Fluid Dipstick (Out of
View). See “Checking the Fluid Level” under
Automatic Transmission Fluid on page 401.
F. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 394.G. Radiator Pressure Cap. SeeRadiator Pressure
Cap on page 408.
H. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 394.
I. Remote Negative (−) Terminal (Marked GND).
SeeJump Starting on page 423.
J. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 419.
K. Battery. SeeBattery on page 422.
L. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 493.
391