Ford 1998 Windstar Owner's Manual page 209

Have the exhaust and body ventilation systems checked by a
qualified technician whenever:
your vehicle is raised for service
the sound of the exhaust system changes
your vehicle has been damaged in an accident
If the exhaust system has any indications of leaks it should be
repaired immediately.
Improve your ventilation by keeping all air intake vents clear of
snow, leaves, and other objects.
If the engine idles while you are stopped in an open area for
long periods of time, open the windows at least one inch. Also,
adjust the heating or air conditioning to bring in outside air.
Read the section Climate Control Systems for instructions on
bringing fresh outside air into your vehicle. Refer to the Index.
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