I'm looking around for a 2004-2011 Grand Marquis. Since they're all older cars, what problems should I look for?
I own a 2005 Mercury Grand Marquis. So far I have put 10,000 miles on it, the only issues I have run into is replacing the Lighting Control Module (LCM) and that is a recall a Ford sent out so I fixed that for free. Otherwise it's a fun car, you can drive how you want without worrying because these cars are built like tanks! I bought my car at 69,000 miles. But do not buy a Grand Marquis that has been sitting for awhile. I bought my car after it sat outside for over a year without being used, but the body looked pristine so I wasn't worried about it. Little did I know the oil pump was rusted and fell off and my engine blew out. Had to get it replaced, thankfully it was replaced with a lincoln towncar engine which means it was most likely elderly driven.
They're pretty reliable cars but have a mechanic check out potential candidates. Problems with the HVAC system are difficult to repair, usually requiring removal of the entire dashboard. If possible try to determine if the heater core or evaporator are leaking. (Heater core will generally cause an antifreeze smell and window fogging in the car. You'd need a refrigerant detector to check the evaporator, but suspect it if AC is not working or weak.)
The blend door actuator is a frequent trouble spot. It's supposed to be repairable without removing the dash but is still a sporting proposition.
https://www.youtube.com/watch?v=7RFH0Ue-bnQ
I looked at the owner reliability complaints and from about 2003 on they decrese as the model year goes on:
https://www.carcomplaints.com/Ford/Crown_Victoria/
https://www.carcomplaints.com/Mercury/Grand_Marquis/
The thing is, you want one that was cared for and maintained. Stay away from cop cars or stuff like that. You could easily find one with low miles owned by a grandpa which could be an excellent find. The only "common" problem I could find was the mid 2000s model years where the "HEAD LIGHTS TURN OFF WHILE DRIVING."
Also I don't have experience with a Panther car but this is information reported from owners of the cars. Some people above also reported the lighting control module so that is something "common" but it isn't anything that major just have a mechanic check one out with lower miles. JamesE also has a good point were you should not get one that old I would say look for a 2007 or newer.
Almost nothing except bad maintenance. 2011 cops complained about headrest and sore necks. Avoid cop cars or taxis, look for 30k-70k miles, 03-10 common, 2011 pretty rare, avoid older than 03. Good ones are really hard to find.
So I'm just going to hit the items specific to this car and not all the other things you should check when buying a car:
1. Intake manifold leaks. Look for coolant around the thermostat housing or where the heater core hoses connect. Known to be a routine replacement for most around 150,000 miles. Use only the Ford parts, the aftermarket ones have been nothing but junk and headaches for those that used them.
2. Lighting control module. Located easily under the dash above the gas pedal. Many have had their relays changed from 10A to 15A. You can pull the two connectors, slide it out, open it easily and check the relays pretty easily. You may have to Google the relay # to see the rating OR it's obvious on the back side of the board if a new solder job was done.
3. 2004 is the last year of drive-by-cable. The cars went to drive-by-wire in 2005. The digital portion of 2006+ car's instrument cluster tend to burn out.
4. Automatic hvac controls (digital unit). There are four or six rubber o-rings that dry out and leak causing all the air to default to the defroster. A package of new silicone o-rings is like $2 on Amazon. Takes about 30 minutes to do the whole job. Lots of YouTube videos on how to do it and its very easy to do yourself; unless you like spending $500 on a new unit with old rubber o-rings that's been sitting on a parts shelf somewhere. I went through this.
5. Blend door actuator position. The foil trace or the gears in the actuator fail/wear out. There is a way to do this through the glove box/passenger air bag area. See YouTube videos.
6. The blend door moves on a flexible plastic hinge that tends to just break off over time.
7. In climates with snow/rain, the steering shaft joints tend to go out; check to see if the wheel is hard to turn, jerky or doesn't return. Also in the later cars there is a green clip in the steering shaft inside the car. They tend to crunch and fail; there is a recall to replace it as you'll lose full steering when driving.
8. I've noticed bunches of Grand Marquis with failing pinion seals; probably from sitting so much. I went through this.
9. The engine fan module sometimes is known to fail. Make sure it runs with the a/c off. With the a/c set to MAX, it should always run. I believe it runs in two speeds, low and high.
10. Avoid at all cost one in white or the silver colors; they are most prone to heavy peeling due to poor primer application. White is the worst of all. The lighter colors used a different primer than the dark colors. Dark colors are better; like dark blue, red. It's not a question of if the light color will peel off, but when.
Otherwise, the cars are very strong, basic, and easy to work on with basic hand tools as the design of everything really dates back 30 years. 2003+ are the best years; they got rack/pinion steering, fully boxed frames, the last power boost out of the engine, rear shocks moved to the outside of the frame rail, 16" or 17" wheels to fit the larger rotors. Check out http://www.crownvic.net for more. Lots of aftermarket performance parts like http://www.adtr.net
