Honda 2009 Ridgeline Owner's Manual page 364

Vehicle Storage
Cover the vehicle with a
''breathable'' cover, one made
from a porous material such as
cotton. Non-porous materials, such
as plastic sheeting, trap moisture,
which can damage the paint.
If possible, periodically run the
engine until it reaches full
operating temperature (the
cooling fans cycle on and off
twice). Preferably, do this once a
month.
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