1984 CHEVROLET CAVALIER catalytic converter

Downloaded from www.Manualslib.com manuals search engine FUEL REQUIREMENTS
Your engine is designed to use Only unleaded gasoline. Unleaded gasoline
must be used for the emission control system to operate properly. Its use will
also reduce spark plug fouling, exhaust system corrosion and engine oil deterioration.
Using leaded gasoline can damage the emission control system and could result in loss of emission warranty coverage. The effectiveness of the catalyst in the catalytic converter decreases after use of as little as one tank of leaded
gasoline. Also, your vehicle may have the "Computer Command Control"
system, which includes an oxygen sensor. Leaded gasoline will damage the sensor, and deteriorate emission control. (For more information, see
"Computer Command Control System" in "Service and Maintenance," Section 5 of this manual).
Federal
regulations require that pumps delivering unleaded gasoline be labeled with the word UNLEADED. Only these pumps have nozzles which fit the filler neck of your vehicle's gasoline tank.
In the United States, Federal law also requires that gasoline octane ratings be
posted on the pumps. The octane rating shown is an average of Research (A)
octane number and Motor (M) octane number. In most parts of the United
States, you should use unleaded gasoline with an octane rating of at least 87. However, you may use unleaded gasoline with an octane fating as low as 85 in these high-altitude areas: Colorado, Montana, New Mexico, Utah, Wyoming,
northeastern Nevada, southern
Idaho, western South Dakota, and that part of
Texas which
is directly south of New Mexico.
Using
unleaded gasoline with an octane rating lower than stated above can
cause persistent, heavy "spark knock."
("Spark knock" is a metallic rapping
noise.) If severe, this can lead to engine damage. If you detect heavy spark
knock even when using gasoline of the recommended octane rating, or if you hear steady spark knock while holding a steady speed on level roads, have
your
dealer correct the problem. Failure to take steps to stop such knocking is misuse of the vehicle, for which Chevrolet is not responsible.
However, now and then you may notice light spark knock for a short time while
accelerating or driving up hills. This'is no cause for concern, becauseyou,,~et the greatest fuel economy benefit from the gasoline's octane rating when there
is occasional light spark knock. Using gasoline with a higher octane rating than
that which allows occasional spark knock is an unnecessary expense.
Gasoline/Ethanol Blends
Blends of unleaded gasoline and ethanol (grain alcohol) sometimes known as gasohol are available in some areas. You may use these blends in your
vehicle, if they are no more than 10 percent ethanol, without jeopardizing the New Vehicle and Emission Warranties. Be sure the gasoline-ethanol blend has
octane ratings no lower than those recommended for unleaded gasoline. Most
drivers
will not notice operating differences with blends of up to 1 0 percent
ethanol, but some may. In that case, your authorized dealer can make certain
adjustments, provided they
do not violate the Federal Emission Standards. If you are still not satisfied with ethanol-gasoline blend performance, you may
prefer
to use unleaded gasoline.
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Downloaded from www.Manualslib.com manuals search engine NOTICE: H you need to replace the fuel cap, use only a cap specified for your model. An incorrect fuel cap can result in a serious maHunction of the fuel system or emission control system. You can get a correct replacement cap from your dealer.
CATALYTIC CONVERTER
The catalytic converter is an emission control device added to the exhaust system to reduce exhaust gas pollutants. The converter contains
a ceramic material coated with noble metal catalysts. To prevent contamination
and loss of effectiveness of the catalysts. unleaded gasoline must be used.
Unleaded
gasoline also reduces spark plug fouling, exhaust system corrosion and engine oil deterioration. Leaded gasoline will also damage the oxygen
sensor
in the Computer Command Control system which could affect emission
control.
To help prevent damage:
1. Keep your engine properly maintained. Engine malfunctions involving the
electrical, carburetion, electronic fuel injection or ignition systems may
result in unusually high catalytic converter and exhaust system
temperatures which, under extreme malfunctioning conditions, may ignite
interior floor ·covering materials above the converter. Do not keep driving
your vehicle if you detect engine misfire, noticeable loss of
performance, or other unusual operating conditions. Instead, have it
serviced promptly. See the Maintenance Schedule folder for information on inspecting and maintaining the engine, exhaust system, and other
components.
2. Do not push or tow this vehicle to start it. This may result in unusually
high catalytic converter
and exhaust system temperatures which under
extreme conditions may ignite interior floor-covering material above the
converter.
Disregarding these instructions
could damage the catalytic converter, the vehicle, or nearby property and affect warranty coverage.
COMPUTER COMMAND CONTROL SYSTEM
Most vehicles sold in the United States (and some vehicles sold in Canada)
have the Computer Command Control system.
The Computer Command Control system monitors the exhaust stream with
an oxygen sensor. Based on sensor signals, the electronic control module adjusts
the air-fuel ratio
as needed. It is very important to use only unleaded
gasoline in vehicles equipped with the Computer Command Control system.
Leaded gasoline will damage the oxygen sensor,
and may affect emission
control.
"Check Engine" Light
Most vehicles sold in the United States (and some vehicles sold in Canada)
have the Computer Command Control system.
Vehicles
.with the Computer Command Control system, include a "CHECK
ENGINE" light
on the instrument panel designed to indicate the need for
system service. It will come on during engine starting to let you know the bulb
is working. (The
light will stay on a short time aiter the engine starts.) Have the
system repaired if the "CHECK ENGINE" light does not come on during engine
starting.
If the light comes on, either intermittently or continuously while driving,
service to the Computer Command Control system is required. Although in
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