2007 BUICK LUCERNE engine overheat

Service........................................................ 325
Accessories and Modications................... 325
California Proposition 65 Warning.............. 326
Doing Your Own Service Work.................. 326
Adding Equipment to the Outside of
Your Vehicle.......................................... 327
Fuel............................................................. 327
Gasoline Octane........................................ 327
Gasoline Specications.............................. 328
California Fuel........................................... 328
Additives................................................... 328
Fuels in Foreign Countries........................ 329
Filling the Tank......................................... 330
Filling a Portable Fuel Container............... 332
Checking Things Under the Hood.............. 332
Hood Release........................................... 333
Engine Compartment Overview.................. 334
Engine Oil................................................. 337
Engine Oil Life System.............................. 340
Engine Air Cleaner/Filter............................ 342
Automatic Transaxle Fluid......................... 343
Engine Coolant.......................................... 347
Radiator Pressure Cap.............................. 351
Engine Overheating................................... 351Overheated Engine Protection
Operating Mode..................................... 353
Cooling System (3.8L V6 Engine).............. 354
Cooling System (4.6L V8 Engine).............. 360
Power Steering Fluid ................................. 364
Windshield Washer Fluid........................... 365
Brakes...................................................... 367
Battery...................................................... 370
Jump Starting............................................ 372
Headlamp Aiming........................................ 377
Bulb Replacement....................................... 380
Halogen Bulbs........................................... 380
Taillamps, Turn Signal, Stoplamps and
Sidemarker Lamps ................................. 380
Taillamps and Back-Up Lamps.................. 382
License Plate Lamp................................... 383
Replacement Bulbs................................... 383
Windshield Wiper Blade Replacement....... 383
Tires............................................................ 385
Tire Sidewall Labeling............................... 386
Tire Terminology and Denitions............... 389
Ination - Tire Pressure............................. 392
Tire Pressure Monitor System................... 393
Section 5 Service and Appearance Care
323

How to Check Automatic Transaxle
Fluid (3.8L Engine)
Because this operation can be a little difficult, you
may choose to have this done at the dealership
service department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading
on the dipstick.
Notice:Too much or too little uid can
damage the transaxle. Too much can mean that
some of the uid could come out and fall on hot
engine or exhaust system parts, starting a re.
Too little uid could cause the transaxle to
overheat. Be sure to get an accurate reading if
you check the transaxle uid.
Wait at least 30 minutes before checking the
transaxle uid level if you have been driving:
When outside temperatures are above
90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.To get the right reading, the uid should be at
normal operating temperature, which is
180°F to 200°F (82°C to 93°C).
Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C),
you may have to drive longer.
Checking the Fluid Level
Prepare your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift
lever in PARK (P).
3. With your foot on the brake pedal, move the
shift lever through each gear range, pausing
for about three seconds in each range.
Then, position the shift lever in PARK (P).
4. Let the engine run at idle for three to
ve minutes.
344

Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 351.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to
−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
347

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling
system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system, you
could damage your vehicle. Use only the
proper mixture of the engine coolant listed in
this manual for the cooling system. See
Recommended Fluids and Lubricants on
page 452for more information.
348

Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the coolant surge
tank, but only when the engine is cool.
{CAUTION:
You can be burned if you spill coolant on
hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
Occasionally check the coolant level in the
radiator. For information on how to add coolant to
the radiator, see Index. When replacing the
pressure cap, make sure to turn cap until it clicks.
Radiator Pressure Cap
Notice:The radiator cap on your vehicle is a
pressure-type cap and must be tightly
installed to prevent coolant loss and possible
engine damage from overheating. Be sure
the arrows on the cap line up with the overow
tube on the radiator ller neck.
SeeEngine Compartment Overview on page 334
for more information on location.
Engine Overheating
You will nd a warning light about a hot engine as
well as an engine coolant temperature gage on
your vehicle’s instrument panel cluster.
351

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Turn it
off and get everyone away from the
vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
If you keep driving when the vehicles
engine is overheated, the liquids in it can
catch re. You or others could be badly
burned. Stop your engine if it overheats,
and get out of the vehicle until the engine
is cool.
SeeOverheated Engine Protection
Operating Mode on page 353for
information on driving to a safe place in
an emergency.Notice:If your engine catches re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty. See
Overheated Engine Protection Operating Mode
on page 353for information on driving to a
safe place in an emergency.
If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little too
hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
352

If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to do
so, pull off the road, shift to PARK (P) or
NEUTRAL (N) and let the engine idle.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can idle the
engine for three minutes while you are parked.
If you still have the warning,turn off the engine
and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get
service help right away.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
message ENGINE OVERHEATED STOP ENGINE
is displayed, an overheat protection mode which
alternates ring groups of cylinders helps
prevent engine damage. In this mode, you will
notice a loss in power and engine performance.
This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in
the overheat protection mode should be avoided.
Notice:After driving in the overheated
engine protection operating mode, to avoid
engine damage, allow the engine to cool before
attempting any repair. The engine oil will be
severely degraded. Repair the cause of coolant
loss, change the oil and reset the oil life
system. SeeEngine Oil on page 337.
353

{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak. If
you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.
If there seems to be no leak, with the engine on,
check to see if the electric engine cooling fans
are running. If the engine is overheating, both fans
should be running. If they are not, your vehicle
needs service.Notice:Engine damage from running your
engine without coolant is not covered by your
warranty.
Notice:Using coolant other than DEX-COOL®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
355