GMC 2008 Acadia - Manual (Page 340)

If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
• Climb a long hill on a hot day.
• Stop after high-speed driving.
• Idle for long periods in traffic.
• Tow a trailer.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
3. If you are in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D) or LOW (L).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam, idle the engine for three
minutes while you are parked. If you still have the
warning, turn off the engine and get everyone out of the
vehicle until it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
This emergency operating mode lets your vehicle be
driven to a safe place in an emergency situation. If an
overheated engine condition exists, an overheat
protection mode which alternates firing groups of
cylinders helps prevent engine damage. In this mode,
there is a significant loss in power and engine
performance. The temperature gage indicates an
overheat condition exists. Driving extended distances
and/or 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 system. See Engine Oil on
page 5-15.
5-26