I noticed rough idle on a 2001 MGM and what seemed like transmission slip while going uphill. I replaced the spark plugs. Both problems went away.
how to take the door panel off of a 1997 mercury marquis
Take it to a repair shop.
A grand marquis wiring diagram can be found in a Chiltons or Haynes auto repair manual.
Replace the hose.
Try Autozone.com - they very likely have an on-line illustrated repair guide for the '93 Grand Marquis.
According to my Chilton's Auto Repair manual : A 1988 Mercury Grand Marquis has a ( 20 U.S. gallon ) gas tank
The repair section on autozone.com explains how to change the light switch.
The stereo wiring diagram for a 1988 Mercury Grand Marquis is available from a factory service repair manual. These manuals can be found online and PDF. format.
According to my Chilton's Auto Repair manual : A ( 1987 ) Mercury Grand Marquis has a ( 20 U.S. gallon gas tank )
Need to know what's wrong with it. More info please.
According to my Chilton's Auto Repair manual : For a 1989 Mercury Grand Marquis : With engine oil filter change : Both the 5.0 / 302 and the 5.8 / 351 take ( 5.0 U.S. quarts )
According to my Chilton's Auto Repair Manual : The ( 1987 ) Mercury Grand Marquis holds ( 20 U.S. gallons )