service BUICK RIVIERA 1993 Owner's Manual

If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about ten minutes.
If the warning doesn't come back on, you can drive
normally.
If~the warning continues, pull over, stop, and park your
vehicle right away.
If there's still no
sign of steam, you can idle the engine
for two or three minutes while you're parked, to see
if
the warning stops. But then, if you still have the
warning,
TURN OFF THE ENGINE AND GET
EVERYONE OUT
OF THE VEHICLE until it cools
down. You may
decide not to lift the hood but to get service
help right away.
197

A CAUTION: I
You can be injured if you try to do service work
on a vehicle without knowing enough about
it. I
@ Be sure you have sufficient knowledge,
experience, and the proper replacement
parts and tools before you attempt any
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. $$g?$&$
~~~
vehicle maintenance task. gg@b%j.g ,;.. ,F!(7>>p I &. @fijy+; &~-*.,~<+@ %,.,!+:<$$
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Fuel
Use regular unleaded gasoline rated at 87 octane or
higher: It should meet specifications ASTM D4814 in
the U.S. and CGSB 3.5.92 in Canada. These fuels
should have the proper additives,
so you should not have
to add anything to the fuel.
Use regular unleaded gasoline rated at 87 octane or
higher. It should meet specifications ASTM D4814 in
the U.S. and CGSB 3.5-92 in Canada. These fuels should have the proper additives,
so you should not have
to add anything to the
fuel.
In the U.S. and Canada, it’s easy to be sure you get the
right kind of gasoline (unleaded). You’ll see
“UNLEADED” right on the pump. And only unleaded
nozzles will fit into your vehicle’s filler neck.
Be sure the posted octane
is at least 87. If the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough,
it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
still hear heavy knocking, your engine needs service.
But don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a hill. That’s normal,
and you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem. What about gasoline with blending materials that
contain oxygen, such as MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.” Fuel that is no
more than 15% MTBE is fine for your vehicle.
Ethanol
is ethyl or grain alcohol. Properly-blended fuel
that is no more than
10% ethanol is fine for your
vehicle.
Methanol is methyl or wood alcohol.
217

I
Gasolines for Cleaner Air
Your use of gasoline with detergent additives will help
prevent deposits from forming in your engine and fuel
system. That helps keep your engine in tune and your
emission control system working properly. It’s good €or
your vehicle, and you’ll be doing your part for cleaner
air.
Many gasolines are now blended with materials called oxygenates. General Motors recommends that you use
gasolines with these blending materials, such as MTBE
and ethanol. By doing
so, you can help clean the air,
especially in those parts
of the country that have high
carbon monoxide levels.
In addition, some gasoline suppliers are now producing
reformulated gasolines. These gasolines are specially
designed to reduce vehicle emissions. General Motors
recommends that you use reformulated gasoline. By
doing
so, you can help clean the air, especially in those
parts of the country that have high Ozone levels.
You should ask your service station operators if their
gasolines contain detergents and oxygenates, and if they
have been reformulated
to reduce vehicle emissions.
Fuels in Foreign Countries
If you plan on driving in another country outside the
U.S. or Canada, unleaded fuel may be hard to find. Do
not use leaded gasoline. If you use even one tankful,
your emission controls won’t work well or at all. With
continuous use, spark plugs can get fouled, the exhaust system can corrode, and your engine oil can deteriorate
quickly. Your vehicle’s oxygen sensor will be damaged.
All of that means costly repairs that wouldn’t be covered
by your warranty.
To check on fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you’ll be driving.
You can also write us at the following address for
advice. Just tell us where you’re going and give your
Vehicle Identification Number
(VIN).
General Motors of Canada Ltd.
International Export Sales
P.O. Box 828
Oshawa, Ontario L1H 7N1, Canada
218

When to Change Engine Oil: See if any one of these is
true for you:
Most trips are less than 4 miles (6 km).
a It’s below freezing outside and most trips are less
than
10 miles (16 km).
0 The engine is at low speed most of the time (as in
door-to-door delivery, or in stop-and-go traffic).
Most trips are through dusty places.
If any one of these is true for your vehicle, then you
need to change your oil and filter every
3,000 miles
(5 000 km) or 3 months -- whichever comes first.
If none of them is true, change the oil every 7,500 miles
(12
500 km) or 12 months -- whichever comes first.
Change the filter at the first oil change and at every
other oil change after that.
Engine Block Heater: An engine block heater can be a
big help if you have to park outside in very cold
weather, -20
OF (-29 C) or colder. If your vehicle has
this option, see ?Engine Block Heater”
in the Index.
What to Do with Used Oil:
1
Used oil can be a real threat to the environment. If you
change your own oil, be
sure to drain all free-flowing oil
from the filter before disposal. Don’t ever dispose of oil
by pouring it on the ground, into sewers, or into streams
or bodies
of water. Instead, recycle it by taking it to 2
place that collects used oil. If you have a problem
properly disposing
of your used oil, ask your dealer, a
service station or a local recycling center for help.
227

Air Cleaner
As you face the front of the vehicle, the air cleaner is in
the front right section of the engine compartment. There
is a filter inside the air cleaner.
Refer to -the Maintenance Schedule
to detemine when
to replace the air filter.
A I
A CAUTION:
Operating the engine with the air cleaner off can
cause you or others
to be burned. The air
cleaner not only cleans the air,
it stops flame if
I the engine backfires. If it isn’t there, and the
engine backfires, you could be burned. Don’t
drive with
it off, and be careful working on the
engine with the air cleaner off.
I
the air cleaner is off, a backfire can cause a
See “Scheduled Maintenance Services” in the Index.
228

Automatic Transaxle Fluid
When to Check and Change:
A good time to check your automatic transaxle fluid
level is when the engine oil is changed. Refer to the
Maintenance Schedule to determine when
to change
your fluid. See “Scheduled Maintenance Services” in
the Index.
How to Check:
Because this operation can be a little difficult, you may
choose to have this done at a Buick 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.

When to Check: Check your tires once a month or
more.
Don’t forget your compact spare tire. It should be at
60
psi (420 kPa).
I
How to Check: Use a good quality pocket-type gage to
check tire pressure. Simply looking at the tires will not
tell you the pressure, especially
if you have radial tires --
which may look properly inflated even if they’re
underinflated.
If your tires have valve caps, be sure to put them back on. They help prevent leaks .by keeping out dirt and
moisture.
Tire Inspection and Rotation
To make your tires last longer, have them inspected and
rotated at the mileages recommended
in the
Maintenance, Schedule. See “Scheduled Maintenance
Services”
in the Index.
r-
Use this rotation pattern.
After the tires have been rotated, adjust the front and
rear inflation pressure
as shown on the Tire-Loading
Information label. Make certain that all wheel nuts are
properly tightened. See “Wheel Nut Torque”
in the
Index.

Buying New .Tires
To find out what kind and size of tires you need, look at
:the Tire-Loading Information label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
:get ones with that same TPC Spec number. That way,
*your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by a
“MS’,
(for mud and snow).
;If you ever replace your tires with those not having a
!.TPC Spec number, make sure they are the same size,
load rdnge, speed rating and construction type (bias,
bias-belted or radial) as your original tires.
, A CAUTION:
Mixing tires could cause you to lose control
while driving.
If you mix tires of different sizes
or types (radial and ‘bias-belted tires), the
1 vehicle may not handle properly, and you cou’ ’
have a crash. Be sure to use the same size ana
type tires on all four wheels.
It’s
all right to drive with your compact spa
though. It was developed for use
on your
vehicle.
~1
Uniform Tire Quality Grading
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles~ sold.in the United States.)
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded
150 would wear one and a half
248

(1 1/2) times as well on the government course as a tire
graded
100. The relative performance of tires depends
upon the actual conditions of their use, however, and
may depart significantly from the norm due to variations
in driving habits, service practices and differences in
road characteristics and climate.
Traction - A, B, C
The traction grades, from highest to lowest are: A, B,
and C. They represent the tire’s ability to stop on wet
pavement as measured under controlled conditions on
specified government test surfaces of asphalt and
concrete. A tire marked
C may have poor traction
performance.
Warning: The traction grade assigned to this tire is based
on braking (straight-ahead) traction tests and does not
include cornering (turning) traction.
Temperature - A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire
to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure. The
grade
C corresponds to a level of performance
whicrall passenger car tires must meet under the
Federal Motor Vehicle Safety Standard
No. 109. Grades
B and A represent higher levels of performance on the
laboratory test wheel than the minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
I
excessive loading, either separately or in combination, !
can cause heat buildup and possible tire failure.
Those grade
b are molded on the sidewalls of passenger
car tires.
While the tires available as standard or optional
equipment on General Motors vehicles may vary with
respect to these grades, all such tires meet General
Motors performance standards and have been approved
for use
on General Motors vehicles. All passenger type
(P Metric) tires must conform to Federal safety
requirements in addition to these grades.
249