Just got an 02 Grand Marquis with 91k miles. It needs a little bit of work, but over all it's not bad. I'm a little familiar with the 4.6 2v from a Mustang I had a few years back. Generally a Ford guy. I've got a 94 Ford Probe GT, I've had for 9 years, JDM Mazda engine swapped, still a lot of fun, not really a good daily. I'm here to tastefully mod this Grand Marquis, clean it up a bit. See where it goes from there. Manual swap, aluminum factory wheels, Terminator 4v swap, with marauder trim would be great, but then there's reality

 

Hello, and WELCOME !
Your Merc is newer than mine, so ALL the stuff I did will not apply -- but a lot of it is interchangeable with later years.
My '95 is set up for long-distance, hi-speed touring of the Western mountains and deserts.
The Grand Marquis is a great touring car (when set up for touring), but any notions of building a powerhouse engine
for the 2-ton car should be quickly flushed from your mind, as it would cost a lot of time and money -- and you probably won't like the results.
Somewhere on this site (probably on page 2 or 3 of the Grand Marquis section) is a list of the mods I made, with brand names and part numbers for most parts/accessories.
I bought my '95 in '05 -- it had 51,000 miles on it -- now at 155,000 miles and still running strong.
I'll be glad to answer any questions or help in any way.

 

Well as it turns out, the car I bought is a 00 model not an 02. I only found out when I read the title. The ad for the car was written by Grampa, who didn't drive or own the car. Not a big deal, it's only a little disappointing. Still a good car, still low mileage and it was a genuine mistake, they have 7 Grand Marquis in the family soo, easy to get some numbers crossed. Underhood it's dirty, never been cleaned. Today I found out I can fit 2 American Standard toilets, in box, in the back seat and close the doors 0 in the trunk because of the shape of the boxes vs. trunk dimensions. Once I get all the maintenance and repairs done. I'm looking to swap in factory duals with the straight chrome tips. I can't seem to find a set of headers for this car, street legal, emissions legal, headers. Unless long tube headers are somehow compliant!?! Nevermind the sticker shock for headers. I'd also like to make sure there's a working limited slip in the rear, maybe change gear ratios. We'll see. If I keep it long enough manual swap with PI heads and intake. Maybe some Mockrauder body mods. It will still have the Landau top. It's not so easy finding info on modding these, beyond a few specific things.

 

OK, I'll try this one more time --
Headers on a 4,000 lb. vehicle with a stock-cammed engine is a BAD IDEA for a bunch of reasons -- as in fit problems, clearance problems, under-hood heat, limited benefits, cost effectiveness, and plain old common sense. To get the most bang for your bucks, your best bet would be a set of duals by Walker Exhaust -- Walker H-pipe and tailpipes with MagnaFlow glasspacks.(available at Amazon.com).
Spark Plugs -- BOSCH #9606 -- gapped at .054 -- Amazon or Rock Auto
Differential -- TRAC-LOC (Ford) available at Summit Racing or Amazon.
Transmission -- B&M Shift Improver Kit -- Summit Racing or Amazon
Quarter-mile = 16.2 @ 88.6 mph

 

I get what you said about GM not being a performance vehicle. I wanted headers for just a little bit more than what it comes with and for the sound. The stock logs will have to do. I will however be putting in an H-pipe and duals if I can find the right chrome straight pipes, not the ones that turn down at the bumper. I just put some Motorcraft plugs in it replaced a bad coil, the rest looked okay. The CEL went off on it's own and the single misfire was the only code in there. Just put new rotors and pads on the front, for a BIG improvement in stopping. 95 MERC do you know anything about the keyless entry on 00 GM. I'm looking to factory remote this thing. As it is at the moment the power locks do not work. It had an aftermarket alarm, that has since been disabled.

 

I used a pair of Walker tailpipes with the turn-down part cut off and replaced with a short section of straight pipe.
Picture of rear of my car shows Superior chrome, angle-cut, rolled-edge tips -- with notches in bumper that allow for more ground clearance and a smoother over-all appearance.
I designed the dual exhaust system, bought the parts, and fit it all together -- before having it all welded up at a local muffler shop. TOTAL cost was under 300 dollars.
The MagnaFlow glasspacks were chosen for their straight-thru, no louvers, maximum-flow design -- and their low cost -- and the exhaust sound is powerful without being NOISY.
Seems like there are a lot of young fellas that believe that decibels = horsepower, but that's kid stuff.
The MotorCraft plugs were a good choice -- IF the proper type was chosen. The Factory Shop Manual specifies that ONLY the DOUBLE-PLATINUM type be used, as the SINGLE-PLATINUM type will fail after 30,000 - 40,000 miles.
I've experimented with several different plug brands, and found the best all-around performance and fuel mileage comes from the BOSCH DOUBLE-IRIDIUM #9605, which is best for the '92-'95 models, and the #9606 is best for the later years.
Your power-door-lock system was probably laid low by the joker that installed the Alarm System -- it's a COMMON problem with all brands of cars/trucks. A cheap alarm system that is poorly installed is guaranteed to cause goblins in the electrics.
Word of advice-- Disconnect the NEGATIVE battery terminal BEFORE doing ANY work on your car's electrical system.