2004 GT1 poor gas mileage

I have a 2004 Grand Am GT1 with the 3.4 L engine. My gas mileage has always been lower than I would like, but with the cold temps lately in Iowa it has dropped even lower. In the summer I could run around 27-28 only highway driving, in town mixed with highway only around 25. The cold weather has dropped my mileage down to around 23-24 mixed town and highway driving. My wife drives the car most of the time and doesn't treat it like a racecar. Is this typical for this car?

I can tell the car is geared down for power and acceleration but for a V6 in that size of car I would expect better mileage. I have around 55,000 miles trouble-free on the car.

What can I do to improve the mileage?

Thanks guys

hey. just thought you'd like to know that in the winter, most gasoline companies include a higher amount of ethanol to prevent gas line freeze up. but if you still want to increase MPG...there are a lot of things you can do.
-replace O2 sensors
-short ram or cool air intake
-replace glow plugs
-clean or replace fuel injectors and fuel pump
-clean or replace fuel filter
and the list goes on...

I would dis agree with the CAI as the colder the incoming air the more fuel you will use.
Plus you can get a little icy on your TB and MAF when realy cold, below 30 deg.

Also with that little of a drop it could just be from letting it run to warm up causing the mpg to drop.

My 99 GT has dropped about 4-5mpg since it's been in the 30's.
But that's driving it like a race car. :lol:

IMO , I wouldnt do anything unless it needs to be replaced.

Even the warmer weather running I would like to see a little higher if I could, I'm sure letting the car warm up has hurt me in the cold weather. So is the mileage I am getting pretty typical for this car/engine?

If there isn't anything wrong with my O2 sensors, fuel pump, injectors, etc I can't see spending the money to replace those. I thought I would replace the fuel filter and run some injector cleaner through just as regular maintenance. Are there aftermarket parts available that can change the MPG?

Any other recommendations without spending a lot of cash replacing major parts?

Thanks again
Bob

Never hurts to change the fuel fitler, they realy should be changed ever 10-20k miles.
Injection cleaner wouldnt hurt either, these cars are prone to injector clogs and overall failure(s). GM does recomend doing a full fuel system cleaning regularly via the shradder valve on the fuel rail. Napa sells a fuel syst cleaning kit, costs about $300 but will work for most SFI autos.

You can test your O2s to see if they are working with in tollerance.
The best way IMO would be to use a high quality scan tool to watch the data streams whike warming up and at running temp.
But you can manualy test them, here is a link that'll help with that, though being an 04 neither should realy be bad but you never know.

Oxygen Sensor- 99+ Grand am - Testing and replacement (http://www.automotiveforums.com/vbulletin/showthread.php?t=672110)

Very typical! I have a 2000 grand am GT. In the summer on long trips, I struggle to get 27-28mpg. In the winter I get 22-24. I do make a lot of short trips in the winter though. Only 11 miles to work, then 11 miles back. I live in Wisconsin.

I miss my old 95 grand am GT(3.1 v6). I could get 30-33mpg on that thing on longer trips. Although I did get 11mpg once while in HS and beating on it during my half mile trip to school. The tank lasted me a month and a half though!