Replace the sensor. There are two types for 1996-earlier rigs - make sure you specify whether you have a lamp or a gage on your panel (if you don't see a gage, you have a lamp.)
The connector and rubber boot should just pull right off - it's a standard 1/4" "spade" style quick-disconnect.
Be sure to clean the connector before you put it back on - a quick black of electrical contact cleaner (best), brake cleaner (better), or carburettor cleaner (OK) will usually do. If you need to reterminate because the connector is too contaminated to clean, use a 1/4" female "spade" style quick-disconnect (standard part, available pretty much anywhere.) Get one with an insulating boot.