What's your actual MPG?

I just bought a 2004 with 60k a few weeks ago at i have calculated that MPG is 11.4. That is horrible for a 3.8! I can watch the guage move on short trips! I have no fuel leaks and the car runs great so what's the deal?

I get 25 mpg on almost every tank with a commute of 50 miles one way on rural highways. I'd say you have a bad problem and I don't have a clue. I'd start with new plugs, wires, and injector cleaning.

ease up on the gas a bit then, something must not have been calculated right, I'm getting 28mpg on rural roads, no mods, just k&n filter. but never have the car over 3000 rpms

Just did a road trip with a 02 w/55,000 and was able to squeeze 29mpg. The city drive is more like 20mpg.

Something is going on. I have a 2000 GP SE with a 3.1 with 93K and I get 22-23 mpg around town and about 30-32 highway, and that's with a slight misfire on cylinder 1.

i average 22-23 w/ mixed driving, some spirited driving, and just took a 600 mile round trip a couple weeks ago, hit 28 mpg at a steady 80 mph...

I have a 2000 gtp with 84,000 and I get 22.5 consistantly with all city driving

I guess i'll run through the usual suspects ie plugs, o2 sensor, air filter.... Haven't had much time to mess with it, this car is a rushed replacement for my only other car that just died. Trying to get it running asap to sell it!

Take it to Auto Zone or Advance and have it scanned, instead of guessing. It certainly won't hurt...

Well i dont know if the Computer in the inside or the Car is( right), But i go across states all the time and i will reset it on the highway a a steady speed, and i can pull 35 mpg if i stay below 75 with Curise on. Like i took a 340 mile trip and at the end of the trip i had 1/4 tank if< but that problay b/cuz when i fill my car up i alway go the the next dollar if its full about 40.23 i will just keep goin to 41.00 ( gas is high right now) i put 47 in my 2002 Gp GT, last week ( gas was 3.02) Dallas,TX

11.4 mpg?? :shakehead

My '97 GTP is moderately modded and I get better than that. My DIC and manual calculation are very close. See below. Proof is in the pudding. :lol:

http://i5.photobucket.com/albums/y186/lizzywiz/dicfuel.jpg

The '04 and up models should be getting much better than that.

http://www.fueleconomy.gov/feg/noframes/19798.shtml

i have a 2000 SE with the 3.1 with 75K on it, with all city i get 21, with all highway on cruise at 79 i was getting 33. only thing i have done to it is a K&N factory drop in filter

1997 GP GT w/111,500 no mods I get 33 highway 20 city. Keep us posted when you find out whats causing your bad MPG

so bad news, when I'm on the freeway and really using the supercharger but not really getting above 80, I can get 18mpg, but when I lay off the supercharger and slowly accelerate, I traveled for 4 hours last weekend and got 30mpg, once when I was stuck doing 55, I managed 39mpg, but around town, I can at best get 17, but if I'm hotting it around, about 9 or 12! so, sadly enough, it depends on how mellow you are driving, and I'm doing all this with a smaller pulley, I'm thinking about putting on a much larger one now ; !!

1997 GP GT w/111,500 no mods I get 33 highway 20 city. Keep us posted when you find out whats causing your bad MPG


How fast you driving 55/60?

I get....
75/80mph 25/26mpg.
65/70mph 27/28mpg.
55/60mph 29/30mpg.

Intown 17/20

Best I ever got was 31.3 going 60 when I first got the car @73K

What is it? A GT, GTP, base model? I have a 2004 GTP CompG and I get around 20-21 mpg in city.

On the highway traveling at around 80 mph, last night I was getting around 24-25 mpg. If I traveled at around 75, it would read at around 27-28 mpg.

You already hit 60k, so the warrranty is void huh? Or did you purchase the extended?

It's a 04 GT with 60k. I drive mostly city, short commutes. It's about 10 miles to work and i usually get it up to 55 max for short durations. I've been keeping it under 3000 rpm at take off to see if maybe a heavy foot was causing the excessive fuel consumption but no improvement. I did buy the car with 60k on it and it was driven cross country alot, it was owned by a sales company and used by salesmen to travel.

It's a 04 GT with 60k. I drive mostly city, short commutes. It's about 10 miles to work and i usually get it up to 55 max for short durations. I've been keeping it under 3000 rpm at take off to see if maybe a heavy foot was causing the excessive fuel consumption but no improvement. I did buy the car with 60k on it and it was driven cross country alot, it was owned by a sales company and used by salesmen to travel.
Maybe the bad gas mileage was the reason he dumped it. Surely there is something wrong that can be repaired to get it up to 25 mpg.

I'm not a mechanic by any means, so sorry but I'm stumped! I wish I could help!

Mine is terrible.14MPG in the city while granny driving.

How fast you driving 55/60?

I get....
75/80mph 25/26mpg.
65/70mph 27/28mpg.
55/60mph 29/30mpg.

Intown 17/20

Best I ever got was 31.3 going 60 when I first got the car @73K

My car has 86,000 miles and I just replace both O2 Sensors and put both new belts (Gatorback :thumbsup: ), a new 180 Tstat and air filter. I was getting pretty bad MPG (City 12/15, Hyw 20/25). and now I'm getting City 18/23, Hyw 25/30. HUGE improvement.

I have everything stock and now everything is running smooth. Better idle and seems to have more power. Plugs and cables were replaced at 70,000.

By the way Bob, that cabin air filter from the Regal, fits like a glove!!

Special thanks to bnaylor3400, richtazz and GTP Dad for all your help and those handys DIY's :dogpile:

I have a 02 GP GT w\ 60k miles and I get around 25 m\g with mixed driving

I got 28.7mpg going 78mph & with a little intown driving. But..... thats with a 15-20 south wind and I was going north :).

How accurate is the dash computer most of the time on the GT? I remember once it said I could drive 120 miles with the gas I supposedly still had, even though my low gas light was on. Between highway and suburb driving i get 23mpg. (97 GP GT)

I don't have DIC on my 01 GT. During winter, it averages 25-26 mpg between fill-ups (fuel added div. by trip odometer). Summer I do better and average about 26-27mpg. My driving is 3/4 highway @65-70mph.

It is pretty close to the EPA rating of 28mpg highway.

I got a 95 Grand Prix SE with 110,000 miles and I only get 14/16 mpg around town driving. Thats after putting new plugs and air filter in at 105,000. I guess back in 95 they didnt care as much about mileage as they do now with gas prices always on the rise.

how are you calculating the mpg, based off tank size or the actual amount of gallons you put in at fill up?

i consistently drive 80 when on highway and do a lot of city driving with at lead foot and have never got below 23mpg

I always fill my car up to full tank. I calculate my mileage based on the amount of gas I put in. Miles Driven Since Last Fill Up/Amount put in= MPG
Thats how I always calculate mine and I check everytime I Fill up. I wonder if my O2 sensors are in need of replacement, 14-16mpg around town adds up lol.

my 96 se with the 3.1 gets 30 mpg at 65 mph and drops to 27 mpg at 80 mph with the cruise control on for extended drives. out here i often go thru two tanks a day, traveling over 650 miles. my combined city/highway driving when at home avearages over 23 mpg.

one rule i have is to never get below 2 gallons of fuel left. the fuel acts as a coolant for the fuel pump. wouldn't want to get stranded in the desert with a burned out fuel pump. again.

im getting roughly 20mpg with my 2001 Pontiac Grand Prix SE 3.1 V6

I have a 97 GT Modded with 156K and I easily get 21-23 consistently. It's like 17-19 when getting on it everywhere I go.

Sorry guys but this is an old thread and it has out lived its usefulness. Thread closed.