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Resources for the Repair and Maintenance of your 2003 Mercury Grand Marquis

2003 Mercury Grand Marquis

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2003 Mercury Grand Marquis Problems

Engine -- Verified

The composite (plastic) intake manifold may crack near the thermostat housing and cause a coolant leak. Ford released an updated manifold that was reinforced to prevent a recurrence. No recall was issued for this problem but Ford did extend the warranty to seven years on some models from the date of purchase.

Electrical & Lights -- bearmug and 41 others

The car had 64600 miles on it and the headlights started going out while driving, which can be very dangerous. The problem is in the Light Control Module which is an expensive part (around $500 to $600 + labor).

Drive Train -- Verified

Wear on the rear axle shafts near the bearings can create excessive play and lead to gear oil leaking past the seals. Gear oil will leak onto the brake backing plate, brakes, and wheels.

2003 Mercury Grand Marquis Questions and Answers

mercurymarquis2003, 2003 Mercury Grand Marquis, Lakeland, FL

uneven acceleration 50-60mph

erico, 2003 Mercury Grand Marquis, Miami, FL

I have this problem from several weeks, computer is not showing any problem. Sparks plugs and the exhaust seals were replaced and the problem seem to increase. Two years ago the torque converter wa...

dmac, 2003 Mercury Grand Marquis, Anaheim, CA

a heater valve or actuator is malfunctioning. No matter the temp setting and even with the A/C on, the air blows hot. Is this a difficilt repair? What would be an estimate for repair? Can it be don...

todd schmidt, 2003 Mercury Grand Marquis, Santa Rosa, CA

i understand that most places just drain the trans fluid and then replace it with new fluid which still leaves a fairly signifigant amount of used fluid in the trans. One shop I talked to said the...

todd schmidt, 2003 Mercury Grand Marquis, Santa Rosa, CA

most owner's manuals say not to add fuel injector cleaner to the gas, however many people swear by it. Any answers?

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2003 Mercury Grand Marquis Reviews

Two ton a fun! Almost economy car freeway MPG (idling @ 60mph), quiet, relaxed, upscale, bullet proof engine/ drive train, cheaper parts and insurance!

2003+ GS (base car) is the car to get (03+-latest upgrades), change out lighting control module (weak relay-see ebay/forums) run synth 5-30 only and enjoy your V8/281 powered lux cruiser! Bought an 03 for my daughter with 62k on it, one old lady owner for $4000 and daughter loves it-ease of use and comfort. 25+ mpg on freeway, about 20 mpg overall. Truck frame, engine, drive train. Sleeper used car best buy folks that's safe, reliable, cheap to buy used now with low mileage and typically easy use (thanks, old folks) ! No brainer vs high mileage, beat Japanese rig in high demand! Picky Engineer

I BOUGHT A USED 2003 GRAND MARQUEE LS IN JULY 2012. I WAS TOLD THAT THEY (DEALER SHIP) HAD SENT IT TO THE SHOP AND EVERYTHING WORKED FINE .I BOUGHT IT AT ABOUT 7 PM CAUSE I WAS RUNNING LATE AND THEY WERE BOUT TO CLOSE AND MY OTHER CAR WAS NOT RUNNING . I DID NOT TAKE TIME TO DO A ROAD TEST ON IT AND TOOK THEIR WORD FOR IT .WHICH WAS A MISTAKE .NOW TO THE PROBLEM. AS I WAS DRIVING HOME I HEARD A FAINT NOISE AND THOUGHT IT WAS THE TIRES MAKING A NOISE BUT FOUND OUT ABOUT A MONTH IT WAS A BEARING AND AXLE ON THE REAR .I HAD THAT FIXED. WE TRIED TO SET THE MIRROWS AND THEY WOULD NOT WORK. THE FM RADIO WOUL COME ON AND GO OFF IN ABOUT TWO MINUTES AND MIGHT COME BACK ON FOR A FEW MIN. AND SOMETIME IT WOULD NOT COME ON. THE AM WORKED SOME OF THE TIME AND THE CD PLAYER WORKS GOOD .I HAVE A 1998 MARQUEE . WITH 198,000 AND NEVER HAD ANY TROUBLE WITH IT .I THINK THE 2003'S ARE LIMONS SO IF YOU ARE THINKING ABOUT GETTIN ONE I WOULDN'T .THE 2003 I HAVE ONLY HAD 85,000 ON IT GUES I WILL HAVE TO FIX ALL OF THIS STUFF AND I'M NOT HAPPY .

My 2003 Mercury Grand Marquis headlights only turn on when they want to.I think it should be on recall cause in my opinion this is a safety hazard.I can be going down the road at night and they just cut off.This is dangerous.However after spending about $500.00 I have finally found the problem it was the light module.I feel that Ford/Mercury should put this on recall and pay me my money I spent getting it fixed.Irritated in Georgia :\

The 2003 Mercury Grand Marquis has been the most problematic one my family has ever had, and we've had them constantly since the late '70s. This one had electrical issues from the get-go. The door locks and windows and wipers all got funky at least once, and one door lock has never fully functioned. The AC has gone out a few times, the brakes need replacing more often than a NY cabbie's, we've had to replace engine coils at least 4 times, the seatbelts lock in place so you're pinned to the seat---all-around fun. My mother touts its heft as a safety feature, while I feel its safety is diminished if you have to sit in front of the shoulder strap to breathe, or find your brakes wearing down to nubs every other year. It also sheds its grille pieces everywhere so it looks like a toothless creature. It's a comfortable car to ride in for long trips, but it doesn't feel reliable. Thinking back, we did have a fair amount of issues with these cars over the years. Next time I buy, I want another Subaru Legacy, which in 10 years gave me zero problems, not even with the sunroof.
Last note: I got to this site looking for a solution when the rest of my family was stranded in the car and it wouldn't shift gears for them to drive. I found a solution here suggested for a '96 Marquis: pump the brake and wiggle the wheel while you try to shift to Neutral. My story then mistakenly ended up with the '92 Marquis heading, but I want to make sure 2003 Grand Marquis owners know the fix will work for them if their gearshift is stuck in Park. Then, as someone elsewhere suggested, if you can't go to the shop right away, "park" in neutral with the emergency brake so you don't get stuck in Park again.

I have a 2003 Mercury Grand Marquis well first my oil gauge was going up n down i just thought when i crank it up it does that. It kept downing that since September the day i took it to go see whats wrong was October 10 on my way there I was at a red light it made a really loud horrible sound and it quit on me. I just don't know what to do. The dealer ship said it expire because I went over my miles. I really need to find where I can get it fix I have kids to take to school everyday.

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