Dodge 2009 Challenger Owner's Manual page 385

NOTE: Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your exhaust
system. Do not park or operate your vehicle in areas
where your exhaust system can contact anything that
can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may indicate severe
and abnormal catalyst overheating. If this should occur,
safely bring the vehicle to a complete stop, shut the
engine OFF, and allow the vehicle to cool. Thereafter,
obtain service, including a tune-up to manufacturer's
specifications immediately.
MAINTAINING YOUR VEHICLE 383
To minimize the possibility of catalyst damage:
Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
Do not try to start the engine by pushing or towing the
vehicle (automatic transmission only).
Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough
idling or malfunctioning operating conditions.
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