Hummer 2005 H2 - Manual (Page 103)

When starting your engine in very cold weather (below
0°F or
−
18°C), do this:
1. With your foot off the accelerator pedal, turn the
ignition key to START and hold it there up to
15 seconds. When the engine starts, let go of
the key.
2. If your engine still will not start, or starts but then
stops, it could be flooded with too much gasoline.
Try pushing your accelerator pedal all the way to the
floor and holding it there as you hold the key in
START for about three seconds. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briefly but then stops again, do the
same thing, but this time keep the pedal down
for five or six seconds. This clears the extra
gasoline from the engine.
Notice: Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly.
Engine Coolant Heater
Your vehicle may be equipped with an engine coolant
heater.
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.
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