Cadillac 2013 ATS Owner's Manual page 311

Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air
cleaner not only cleans the air; it
helps to stop flames if the engine
backfires. Use caution when
working on the engine and do not
drive with the air cleaner/filter off.
The cooling system allows the
engine to maintain the correct
working temperature.
1. Engine Coolant Surge Tank and
Pressure Cap
2. Engine Cooling Fan (Out
of View)
1. Engine Coolant Surge Tank and
Pressure Cap
2. Engine Cooling Fans (Out
of View)