poor gas mileage?

[gatlandc]

I am getting a little tired of filling up my car, especially with rising gas prices. The window sticker say this vehicle should do 17mpg city 23mpg highway but I have never go better than 14mpg city, 20mpg highway. Does everyone else have this experience? I would really like to get back the extra 3mpg or 50miles per tank , Any suggestions???

[L.Mark]

I drive mine @60miles a day and get with mixed driving of expressway and city @ 21mpg. I have hit 22mpg once or twice with keeping my foot under control. Mine is also bone stock. If you feather the gas coming off a light and no hard braking or braking at the last minute you will better your gas mileage. The only big jump I've seen is not going over 70 miles an hour. Do the posted(no matter how boring it is) and the MPG should rise. As for add ons, I'll let the experts chime in on that cause I'd like to hear it too. Plus like Curless has said in other posts, you have a 4200lb performance car...

[larryo340]

I bought mine in January with 125k with only mods being K&N air filter in stock box, and accufab throttle body with mixed local and highway dring with a heavy right foot at times I get 19-20 MPG. On a 230 mile one way drive with four people in the car cruising 70-80 MPH I got 24mpg. On a solo run coming back from upstate NY also at higher speeds I got 26 MPG. Needless to say I'm very happy :)

[jus2rel]

I have JLT and tune... I get 13-14 city and 18-19 highway. I have driven it for 7 years now and learned not to care about gas. It's the price I pay for happiness. :banana:

[yjmud]

in stock form I averaged 25 highway traveling 80 mph

[SC Cheesehead]

I am getting a little tired of filling up my car, especially with rising gas prices. The window sticker say this vehicle should do 17mpg city 23mpg highway but I have never go better than 14mpg city, 20mpg highway. Does everyone else have this experience? I would really like to get back the extra 3mpg or 50miles per tank , Any suggestions???

If you've never hit the Estimated Mileage numbers, how can you "get them back?" ;)



Lots of factors affect mileage: Driving style, terrain, regional gas blends, etc.

Do you accelerate and brake smoothly? Do you ride the brakes? What is your average highway speed? Do you warm up your car or leave it idling for extened periods?
How you live in high altitude or hilly terrain?
What octane gas are you using? Do you have to run "winter blend" fuel for a majority of the year?
I average between 14 and 16 in town and between 19 and 22 on the highway (that's with 4.10 gears and SC'd), but I can easily drop those numbers to below 12. My right foot pretty much determines mileage...:D

[RubberCtyRauder]

Original Poster's location says Auckland, New Zealand.. I'm sure not all gas is created equal from US to New Zealand and points in between. It might be that New Zealand gas requirments for emissions etc. do not burn the same as what is formulated here.

Added: Are you using 95RON or 98 RON grade gasoline? 91 RON grade isn't enough octane

[Curless]

Your mileage sounds right on the money...The thought of 24 + on these cars is NOT going to happen. I know some out there claim it but with a scan tool hooked up, monitoring the stats as I drove, the most I have ever gotten was 21...my car does not have the ability to get any more than that.

[Ozark Marauder]

Stock marauder: My experience

Drivin' like an old lady.....:o
City 18.5
Highway 23 - 24.5

Drivin' like it oughta ...:D
City 16
Highway 21 -22

Usually turn into an old lady when the premium (93 octane) hits 4.00 a gallon...:depress:

OZ

[fastblackmerc]

Park the Marauder and get a Prius.

[gdsqdcr]

I run 91, and average ~17.5 in mixed driving. If I am good on the freeway, 21/22 is the new number. I run 4.10's.

Sure I would like it to be better, but then again .... I love driving it.

[Darigaaz]

I'm only getting around 12mpg around the city and 15mpg on the highway. A little irritating as I'm not very heavy footed and typically stick to the speed limit. I just have a K&N filter at the moment.

[MrBluGruv]

Didn't see it mentioned, but remember that tires also play a role in your fuel economy. Proper inflation is one aspect, and some tires simply get worse mileage than either.

[RF Overlord]

Front-end alignment, too...

...and did I miss it? We have a Marauder in En-Zed?

[boatmangc]

+1 on tire pressures.
Best improvement I have done was removing the rear cats. At 55 mph almost 3 mpg after removal.
Problem is I never drive 55, I just did a test on the trip back and forth to the shop, about 20 miles each way at highway speeds.
Let it breathe and put a tune in it is your best bet.
How many miles on your car?
Then simple questions, clean the MAF? Spark Plugs, Air filter?
Maybe a Seafoam treatment followed by an oil change.

[88LTDCV351]

Do you drive like grampa sunday driver? Do you use cruise control when all possible, obey the speed limit (higher speeds are less efficient on gas mileage), drive defensively, coast to a stop when possible, anticipate traffic conditions ahead, at least put the car in nuetral when idling for longer periods, put your seatbelt on before starting the car, etc.?

I've done fairly well when I do that.

[Dave2]

I have JLT and tune... I get 13-14 city and 18-19 highway.


~ I have driven it for 7 years now and learned not to care about gas. It's the price I pay for happiness.



This......^


It doesn't cost that much more to be smiling.......:beer:

[Darigaaz]

I've clean the MAF and the throttlebody, just installed a K&N filter kit with a new filter. I do need new front tires and an alignment so I'll get that done quickly. Fuel filter was replaced at 21k and it is at 60k so I'll swap that out. Getting a tuner in the next few days, I had been having trouble with the way the car shifted so hopefully that will smooth things out.

[Krytin]

I can easily get 24 mpg on highway trips avg. 75 mph (door to door). That's with a very rich N/A tune, JLT intake, glass packs and an Accufab TB.

[MOTOWN]

I've clean the MAF and the throttlebody, just installed a K&N filter kit with a new filter. I do need new front tires and an alignment so I'll get that done quickly. Fuel filter was replaced at 21k and it is at 60k so I'll swap that out. Getting a tuner in the next few days, I had been having trouble with the way the car shifted so hopefully that will smooth things out.

Fuel filter should be replaced every summer at least! your wayyy overdue:depress:

[Darigaaz]

Haha, well I've had the car for a month. I had it in the muffler shop and I checked it out, looks like the lines are pinched near the fuel filter so I'm going to straighten the line out and put a bigger filter on it.

[MOTOWN]

Haha, well I've had the car for a month. I had it in the muffler shop and I checked it out, looks like the lines are pinched near the fuel filter so I'm going to straighten the line out and put a bigger filter on it.

They are all that way from the factory which is why the fuel filter mod came about!

Two fuel lines and a bigger filter to eliminate the factory 90* bends, and kinks.

[gatlandc]

Love all the comments, I forgot to mention I have 4.10 gears and Lidio tune, it's just hit 90,000 miles but I think the real problem is my right foot but I didn't buy a Marauder to drive like my father... Sound like the mileage is about normal.

And yes this Marauder is in NewZealand. Its the only one in the country and gets a lot of looks, mostly by confused people who don't know what it is as the Mercury brand has never been sold in this country, I just tell them its a Ford CVPI.

[JOEMERC]

Switch over to Synthetic fluids if you have not done so will help some also my .02.

[fastblackmerc]

I just tell them its a Ford CVPI.

I like explaining what a Marauder is.......

[RF Overlord]

And yes this Marauder is in NewZealand. Its the only one in the country Do you have the same rules there as in Oz that all cars have to be converted to right-hand drive?

When I was last in Australia (1994) the only car I ever saw that wasn't RH drive was a '65 Riviera at the Buderim Ginger Factory visitor centre in Yandina.

We were followed by a (possibly) '79 Firebird in Launceston Tasmania for a few miles, but it was RH drive.

The older I get, the more I live in my memories... :shake:

[gatlandc]

No thank god, that would destroy it. The NZ rules have changed recently but it use to be you could import a left hand drive if you owned and operated it in the US for 3 months first. Now only "exotic" and performance cars with a manufacturing run of less that 5000 can be imported.

[1 Bad Merc]

You do realize you are driving a Marauder?

I hope you did not buy it for the fuel mileage........Prius or something else would be alot better for that.

Marauder mileage will very depending how much you want to smile that day!!!

Have a great time with the car my friend!

[Motorhead350]

Its broken.

Take the bus.

[JoeBoomz]

I like to measure mine in "Smiles per Gallon"

[Darigaaz]

They are all that way from the factory which is why the fuel filter mod came about!

Two fuel lines and a bigger filter to eliminate the factory 90* bends, and kinks.

So I modded in a bigger fuel filter to replace my 40k mile old one, I changed out the IAC, deleted the EGR, no codes are being thrown but I'm still getting poor gas mileage. I've got a Reinhart tune and that pretty much kept the mpg around the same (unless of course I step on the pedal :D which I rarely do). I know I shouldn't expect 20+ but I would like to get at least 14-16 in the city and a little higher on the highways. I do have a problem with it starting, someitmes it starts right up sometimes it just sputters and dies immediately. I'm going to check my fuel pressure today.

[Nicegy525]

how old are your upstream O2 sensors? Those have alot to do with fuel mileage and lazy sensors can often be overlooked.

[breeze]

After bolt ons I got 230 to a tank. 302rwhp

392 challenger with 470 @ crank 320 to tank 18city 22+ highway

[Darigaaz]

how old are your upstream O2 sensors? Those have alot to do with fuel mileage and lazy sensors can often be overlooked.

I'm not sure. I did delete the rear 02 sensors and disabled the EGR which got me an 18.5 mpg rating with one 150 miles interstate run.

[jsignorelli]

After my dyno tune due to the engine mods, my car gets 22-24 on the hyway. I really don't track around town, but I'd guess that 17-19 is about right.

[Darigaaz]

I've managed to pull 16-17 in the city if I mess around with overdrive a bit. Basically keeping it off until I hit 45-55 mph but I still seem to have a bogging issue I can't quite place.

[tbone]

With the short city trips I take, my heavy foot and a high stall torque converter, I don't even get to 12. Even with that, I only fill up once every 2 weeks on average.

[Spectragod]

With the short city trips I take, my heavy foot and a high stall torque converter, I don't even get to 12. Even with that, I only fill up once every 2 weeks on average.

I'll second that, 7-10 seems normal to me. I can squeeze 17 out of it on the highway if I am easy on it.

[VMARAUDER]

Park the Marauder and get a Prius.

That's right...park it
Car was not made for MPG

[justbob]

Cams and lack of vacuum keeping me in and out of spinning the blower has netted me 8-10 city/ 19 highway when I should easily be seeing 30 now. Not too mention the absolute most ridiculous under hood temps.

I could care less about city as it's only a fun car but I would love to reach my goal of 500 RWHP and low 30's MPG which is so in reach its almost funny.

When she was more tame on the factory block and only 11#'s with the automatic and 4.30's I was quite impressed with 19.8 MPG, but felt I had a long way to go before I was truly happy.




Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

[Vortech347]

Make sure tires are inflated to correct pressure. Set the cruise at 68. Doing these two things will net me 19-20 overall per tank and I have 4.10's.