If you have Climate Control, the Climate Control Unit has gone bad. This is the unit inside of the car that you use to select A/C or heat. It would have a digital readout. You can usually get one from a junk yard for about $100. A new one is over $400. It's very easy to change out.
It will, though technically it is illegal to istall on older motor into a newer car for emissions reasons.
change wiper motor grand marques
how do you get to and replace the wiper moter on a 97 marquis
It is a Mercury and Mercury is a division of the Ford Motor Company so...technically it is a Ford.
( 5 quarts with filter change ) according to the 1999 Mercury Grand Marquis owners manual
I believe you are looking for blend door actuator???
Take it to a repair shop.
5w-30 is what I use in my 2000 grand marquis, in 2001 ford started saying 5w-20.
it is on the firewall and difficult but not impossible to get to and replace.
The 2006 Mercury Grand Marquis owners manual shows : The use of synthetic or synthetic blend motor oil is not mandatory - the oil just has to meet Ford specifications
The 1998 Mercury Grand marquis has the 4.6 liter / 281 cubic inch Single Over Head Cam ( SOHC ) engine from the factory
The relay is located in the engine compartment to the right of the heater hoses if you are looking at them. It dose not look like a regular rely. It has a connector that plugs into it.