FORD 1999 Crown Victoria - Manual (Page 184)

Cleaning the wheels
Wash with the same detergent as the body of your vehicle. Do not use
acid-based or alcohol-based wheel cleaners, steel wool, fuel or strong
detergents. Never use abrasives that will damage the finish of special
wheel surfaces. Use a tar remover to remove grease and tar.
The brushes used in some automatic car washes may damage the finish
on your wheels. Before going to a car wash, find out if the brushes are
abrasive.
Cleaning the engine
Engines are more efficient when they are clean because grease and dirt
buildup keep the engine warmer than normal. When washing:
• Take care when using a power washer to clean the engine. The high
pressure fluid could penetrate the sealed parts and cause damage.
• Do not spray with cold water to avoid cracking the engine block or
other engine components.
• Never apply anything to the drive belt (including belt dressing).
Maintenance and care
184