Engine Coolant Heater
Your vehicle may have this feature.
In very cold weather, 0°F (–18°C) or colder, the
engine coolant heater can help. You will get easier
starting and better fuel economy during engine
warm-up. Usually, the coolant heater should
be plugged in a minimum of four hours prior to
starting your vehicle. At temperatures above 32°F
(0°C), use of the coolant heater is not required.
Your vehicle may also have an internal thermostat
in the plug end of the cord. This will prevent
operation of the engine coolant heater when the
temperature is at or above 0°F (−18°C) as
noted on the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical
cord. The cord is located in the engine
compartment behind the underhood fuse block
on the driver’s side of the vehicle.
3. Plug it into a normal, grounded 110-volt AC
outlet.
{CAUTION:
Plugging the cord into an ungrounded
outlet could cause an electrical shock.
Also, the wrong kind of extension cord
could overheat and cause a re. You
could be seriously injured. Plug the cord
into a properly grounded three-prong
110-volt AC outlet. If the cord will not
reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug
and store the cord as it was before to keep it
away from moving engine parts. If you do
not, it could be damaged.
How long should you keep the coolant heater
plugged in? The answer depends on the outside
temperature, the kind of oil you have, and
some other things. Instead of trying to list
everything here, we ask that you contact your
dealer/retailer in the area where you will be parking
your vehicle. The dealer/retailer can give you
the best advice for that particular area.
123
Fuel
Use of the recommended fuel is an important
part of the proper maintenance of your vehicle.
To help keep the 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 might 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, the engine needs service.
Gasoline Speci cations
At a minimum, gasoline should meet ASTM
speci cation 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. See
Additives on page 326for additional information.
California Fuel
If your vehicle is certi ed to meet California
Emissions Standards, it is designed to operate
on fuels that meet California speci cations.
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
speci cations, 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 192. 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.
326