Why does my gas mileage suck?

[Professor]

Okay, I didn't buy the Merc to be a Prius. Gas prices are coming down and that is nice. However, it seems like other Marauder owners (even with 4.10 gears) get much better gas mileage than mine. If I drive it like a hypermiler (nice easy starts, minimal braking, keeping the rpms down) I get 16 mpg. If I drive it like I stole it (not often) it will drop to 12 mpg. But generally, driving it daily amounts to a consistent 13.5 to 14.5 mpg. I have friends who get 19-21 around town and 28 on the hwy. The only way I could come close to doing that is if I gutted the interior, removed the trunk and bumpers and ... well you get the point.

So ... why is mine so thirsty? It drinks gas like a suburban. Obviously, not something easy to diagnose ... but where would you recommend starting?

[CHSurvivor]

Last time up?alignment? Tire pressure check? Brake service?

[Professor]

Brakes are new. Alignment is new. Tire pressures are normal (38 up front, 36 in back .... yes I know those are high).

[RubberCtyRauder]

How are you calculating gas mileage?..fill the tank, set tripmeter, drive your week, fill up again and divide gallons needed to fill it up into the mileage on tripmeter?

[Zack]

I don't believe the folks claiming 22-24mpg or 350 miles to a tank.
I drive my beater easily and get 300 to a full tank on a good week.
I get 200 to a tank in cold months with winter blend gas

[fastblackmerc]

Good Android app MILEAGE calculates it nicely.

Do you have a tune?

[fastblackmerc]

You will get worse MPG with winter blend gas.

[Comin' in Hot]

I don't believe the folks claiming 22-24mpg or 350 miles to a tank.
I drive my beater easily and get 300 to a full tank on a good week.
I get 200 to a tank in cold months with winter blend gas

I get about 250-280 with my trilogy on the winter blend and have gotten 345 to a tank on a trip at like 70-75, but I have 3.55 gears.

My old N/A marauder with 4.10s got 250-280 with everyday driving and like 320 on a trip.

[Ourobos]

Mine has a tune, I average around 14.5 around town.. They're rated at 17 city.. I noticed today after the first tank of winter blend, I got 13.0... Lovely.. I'd be open for suggestions also. Mine's stock minus mufflers and a tune. Plugs are new, fuel filter is new.

[Baconbit]

I have never gotten 28 mpg on the highway in my MM. I get about 220 or so miles to a tank of just city driving and I have a lead foot. On the highway I get about 19-22 mpg depending on my throttle foot. Thats with add ons and a Mo Tune.

[stevengerard]

Best I ever got was 17 mpg, usually @ 10-12 mpg.

[Mike M]

200 miles per tank, I only drive in town.

[Motorhead350]

23mpg can be done easily if you behave yourself believe it or not.

[a_d_a_m]

I don't believe the folks claiming 22-24mpg or 350 miles to a tank. Would I lie to you? :D

[Motorhead350]

Would I lie to you? :D

He wouldn't believe the truth if he tripped over it. He only believes what wants to believe.

[Fastbob]

http://www.fuelly.com/car/mercury/marauder/2004/1fastbob/329246

Believe it! They will do low to mid 20's. 25 to 28? Not mine.

Most of my miles are Kansas 2 lane at 68 to 71 mph.

[fastblackmerc]

MILEAGE app:

From 9/23/2011 to 12/01/2014

Avg. fuel economy: 15.84 mpg
Worst fuel economy: 11.15 mpg
Best fuel economy: 23.65 mpg
Avg. distance: 228.14 miles
Min. distance: 89.00 miles
Max. distance: 403.00 miles
Est. cost per year: $869.29
Avg. cost per mile: $0.23

[ChiTownMaraud3r]

I averaged 29 hwy after I installed the chin spoiler for a week of 100mi hwy commutes to work when the car was nice and stock.

[RF Overlord]

I have friends who get 19-21 around town and 28 on the hwy. With Marauders? I don't believe that number for the highway. I can get 27 with my DD, but that's with 2.73 gears. The Blackbird got 21 on the way home from Lidio's so I can believe 23-24 with stock gears, but 28 sounds like a fluke.

Lazy O2 sensors can cause poor economy, as can the other things mentioned: tire pressures, alignment, dragging brakes, and especially driving style.

Please don't take offence as I don't know you, but I have lots of friends who would be considered "good" drivers in that they are generally courteous, but they are definitely not good in terms of fuel economy...they don't maintain an even speed and rush up to stop signs then jamb on the brakes. They also follow too closely, needing to constantly brake to keep from hitting people. All of this can drop the gas mileage like a stone.

[Bluerauder]

The best that I have ever done was 24.5 MPG to and from Louisville, KY in 2008. That trip was right at 1,200 miles round trip plus about 250 miles of local travel. I would categorize the trip as a "relaxed" run between 75-80 MPH about half of which was in convoy with other MMs. Don't think I have ever matched that running alone.

[tbone]

Even my lowly 275 hp 03 Deville only gets around 11 or 12 city in this weather.

[RF Overlord]

^^^yeah...winter gas usually reduces economy as well.

[james79stang]

Stock tune when new i was getting 11 mpg in town/23.5 best ever hwy.

After basic tune 15 mpg in town/ 24.5 average hwy.

When I keep with-in easy driving I got 17 mpg in town/25.5 hwy.

With 254k I am getting with easy driving 15 mpg in town/ 22.5 hwy.

Prob need to see how O2 sensors are functioning since they are still the originals!

[shodude]

my best mileage was 25 and worst was 13.2 but I average 18.5. This is coming from my android app Mileage which I've never missed a fill-up and goes back June 6th 2010. average distance is 289miles per fill up. fun fact my largest fill up was 17.46 gallons Ha was running on fumes.

[Bad_S55]

If I drive it like a hypermiler (nice easy starts, minimal braking, keeping the rpms down) I get 16 mpg. If I drive it like I stole it (not often) it will drop to 12 mpg. But generally, driving it daily amounts to a consistent 13.5 to 14.5 mpg.

I just have a lowely 2V, and I get about the same milage. That's with 2.73 gears!! 14.5 mpg is my average, sometimes higher, sometimes lower, but not by much. For what you have, you're not doing too bad man.

[Merc-O-matic]

I get 24-26 on Hwy
20-22 in town.

[tbone]

I just went 56 miles on 8.4 gallons. :burnout: Engine runs flawlessly once she's warmed up. My right foot has issues....

[Bad_S55]

11.9 mpg today :cool4:

[jwibbity]

I just have a lowely 2V, and I get about the same milage. That's with 2.73 gears!! 14.5 mpg is my average, sometimes higher, sometimes lower, but not by much. For what you have, you're not doing too bad man.

you should honestly be getting alot more with a GM with 2.73's, I think somethings wrong.....:confused::confused:

[88CuttyClassic]

23.5 before tune on a highway road trip....and only cause my mom was riding shotgun.

[sailsmen]

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