Miscellaneous Component Or System Checks

WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2003 Mercury Sable, 2003 Mercury Mountaineer, 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

Check the following:

Check PCV system. For Aviator and Mustang 4.6L, go to TEST HG: PCV SYSTEM , step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - CNG, FLEX-FUEL & GASOLINE article. For all others, go to TEST HG: PCV SYSTEM , step 4) under SYSTEM TESTS in SELF-DIAGNOSTICS - CNG, FLEX-FUEL & GASOLINE article.
Check engine mechanical condition. Check valves, valve guides, valve stem oil seals, intake manifold gaskets, cylinder head oil drain passages and piston rings. See appropriate article in ENGINES.