Global Machinery Company Sierra 1999 - Manual (Page 269)

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5-9
Engine Overheating
(Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel. See “Engine Coolant
Temperature Gage” in the Index. In addition, you will
find a LOW COOLANT, CHECK COOLANT TEMP,
ENGINE OVERHEATED and a REDUCED ENGINE
POWER message in the message center on the
instrument panel. See “Message Center” in the Index.
If your vehicle has a diesel engine, see “Engine
Overheating” in the Diesel Engine Supplement.
Overheated Engine Protection Operating
Mode (V8 Gasoline Engines Only)
Should an overheated engine condition exist and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates firing 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. 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 monitor. See “Engine Oil” in the Index.