2003 GMC SONOMA engine

Automatic Transmission Operation
Your automatic transmission has a shift lever on the
steering column.
There are several different positions for your shift lever.
It features an electronic shift position indicator within
the instrument cluster. This display must be powered
anytime the shift lever is capable of being moved out of
PARK (P). This means that if your key is in OFF, but
not locked, there will be a small current drain on
your battery which could discharge your battery over a
period of time. If you need to leave your key in the
ignition in OFF for an extended period, it is
recommended that you disconnect the battery cable
from the battery to prevent discharging your battery.PARK (P):This position locks your rear wheels. It’s the
best position to use when you start your engine because
your vehicle can’t move easily.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brakefirmly set. Your vehicle can roll.
Don’t leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure your
vehicle won’t move, even when you’re on fairly
level ground, always set your parking brake and
move the shift lever to PARK (P). See“Shifting
Into Park (P)”in the Index. If you’re pulling a
trailer, see“Towing a Trailer”in the Index.
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Make sure the shift lever is fully in PARK (P) before
starting the engine. Your vehicle has an automatic
transmission shift lock control system. You have to fully
apply your regular brakes before you can shift from
PARK (P) when the ignition key is in RUN. If you cannot
shift out of PARK (P), ease pressure on the shift
lever–push the shift lever all the way into PARK (P) as
you maintain brake application. Then move the shift
lever into the gear you wish. SeeShifting Out of Park (P)
on page 2-35.
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
seeIf You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-40.
NEUTRAL (N):In this position, your engine doesn’t
connect with the wheels. To restart when you’re already
moving, use NEUTRAL (N) only.
{CAUTION:
Shifting into a drive gear while your engine is
“racing”(running at high speed) is dangerous.
Unless your foot isfirmly on the brake pedal,
your vehicle could move very rapidly. You
could lose control and hit people or objects.
Don’t shift into a drive gear while your engine
is racing.
Notice:Damage to your transmission caused by
shifting out of PARK (P) or NEUTRAL (N) with
the engine racing isn’t covered by your warranty.
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Manual Transmission Operation
Five-Speed
This is your shift pattern.
Here’s how to operate your transmission:
FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal as
you slowly press down on the accelerator pedal.
You can shift into FIRST (1) when you’re going less
than 20 mph (30 km/h). If you’ve come to a complete
stop and it’s hard to shift into FIRST (1), put the
shift lever in NEUTRAL and let up on the clutch.
Press the clutch pedal back down. Then shift into
FIRST (1).SECOND (2):Press the clutch pedal as you let up on
the accelerator pedal and shift into SECOND (2).
Then, slowly let up on the clutch pedal as you press the
accelerator pedal.
THIRD, FOURTH AND FIFTH (3, 4 and 5):Shift into
THIRD (3), FOURTH (4) and FIFTH (5) the same
way you do for SECOND (2). Slowly let up on the clutch
pedal as you press the accelerator pedal.
To stop, let up on the accelerator pedal and press the
brake pedal. Just before the vehicle stops, press
the clutch pedal and the brake pedal, and shift to
NEUTRAL.
NEUTRAL:Use this position when you start or idle
your engine.
REVERSE (R):To back up, press the clutch pedal.
After the vehicle stops, shift into REVERSE (R).
For vehicles equipped with the
VORTEC™4300 V6 engine, you must wait six seconds
before shifting into REVERSE (R). Slowly let up on
the clutch pedal as you press the accelerator pedal.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
Shift to REVERSE (R) only after your vehicle is
stopped.
Use REVERSE (R), along with the parking brake, for
parking your vehicle.
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Up-Shift Light
If you have a manual
transmission, you have a
SHIFT light.
This light will show you when to shift to the next higher
gear for best fuel economy.
When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions let you.
For the best fuel economy, accelerate slowly and shift
when the light comes on.
While you accelerate, it is normal for the light to go on
and off if you quickly change the position of the
accelerator. Ignore the SHIFT light when you downshift.
If your vehicle has four-wheel-drive and is equipped
with a manual transmission, disregard the SHIFT light
when the transfer case is in 4LO.
Shift Speeds
{CAUTION:
If you skip a gear when you downshift, you
could lose control of your vehicle. You could
injure yourself or others. Don’t shift down
more than one gear at a time when you
downshift.
Four-Wheel Drive
If your vehicle has four-wheel-drive, you can send your
engine’s driving power to all four wheels for extra
traction. To get the most satisfaction out of
four-wheel-drive, you must be familiar with its operation.
Read the part that follows before using four-wheel-drive.
SeeOff-Road Recovery on page 4-10.
You should use two-wheel high (2HI) for most normal
driving conditions.
Notice:Driving in the 4-WHEEL HIGH (4HI) or
4-WHEEL LOW (4LO) positions for a long time on
dry or wet pavement could shorten the life of
your vehicle’s drivetrain.
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Shifting Into Park (P)
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brakefirmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle won’t
move, even when you’re on fairly level ground,
use the steps that follow. If you’re pulling a
trailer, see“Towing a Trailer”in the Index.
1. Hold the brake pedal down with your right foot and
set the parking brake.2. Move the shift lever into PARK (P) position like this:
•Pull the lever toward you.
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•Move the lever up as far as it will go.
3. Turn the ignition key to LOCK.
4. Remove the key and take it with you. If you can
leave your vehicle with the key, your vehicle is in
PARK (P).
Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P) with the parking brakefirmly set.
And, if you leave the vehicle with the engine
running, it could overheat and even catchfire.
You or others could be injured. Don’t leave
your vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and your
parking brake isfirmly set before you leave it. After
you’ve moved the shift lever into PARK (P), hold
the regular brake pedal down. Then, see if you can
move the shift lever away from PARK (P) withoutfirst
pulling it toward you. If you can, it means that the
shift lever wasn’t fully locked into PARK (P).
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Engine Exhaust
{CAUTION:
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you can’t see or
smell. It can cause unconsciousness and death.
You might have exhaust coming in if:
•Your exhaust system sounds strange or
different.
•Your vehicle gets rusty underneath.
•Your vehicle was damaged in a collision.
CAUTION: (Continued)
CAUTION: (Continued)
•
Your vehicle was damaged when driving
over high points on the road or over road
debris.
•Repairs weren’t done correctly.
•Your vehicle or exhaust system had been
modified improperly.
If you ever suspect exhaust is coming into your
vehicle:
•Drive it only with all the windows down to
blow out any CO; and
•Have your vehiclefixed immediately.
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Running Your Engine While You
Are Parked
It’s better not to park with the engine running. But if you
ever have to, here are some things to know.
{CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle. See the earlier Caution under
“Engine Exhaust.”
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even if
the fan is at the highest setting. One place this
can happen is a garage. Exhaust—with
CO—can come in easily. NEVER park in a
garage with the engine running.
Another closed-in place can be a blizzard.
See“Winter Driving”in the Index.
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brakefirmly set. Your vehicle can
roll. Don’t leave your vehicle when the engine
is running unless you have to. If you’ve left the
engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle won’t move, even when
you’re on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P).
Follow the proper steps to be sure your vehicle won’t
move. SeeShifting Into Park (P) on page 2-33.
If you’re pulling a trailer, seeTowing a Trailer on
page 4-51.
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