hey hilwayb, do you feel car doesn"t roll like it should on the highway, I have a 2lt with the auto and was also dissiponited with the mpg, my HHR has about 23,000 miles on it and it rolls a little better now, but i am getting about 28-29 mpg mixed on 87 octane.

Wheelie has a 2.4 liter engine, it has been 12 months that he has lived with me, I reset his MPG and now, Wheelie is giving me 25.7 MPG city....Ill check what he gives me in Highway, most likely, alot more:D

YES I DO FEEL LIKE IT DOESN'T ROLL LIKE IT SHOULD.
RIGHT NOW, I HAVE UNDER 3000 MILES ON IT. I HOPE IT IS GOING TO GET BETTER. I AM GOING TO TAKE IT TO THE DEALER IN THE NEXT WEEK OR TWO. THANKS!

Also, I Would Be Estatic With 28-29 Mpg With Mixed Driving!
I Am Only Getting 22-24 Mpg With 70 Percent Highway Driving!

poor fuel mileage
 

I have a 06' 2.4 with Auto. With 21376 miles on her. At 75-80 with A/C on cruise engaged, listening to XM radio am getting between 28.9 to 30.3 MPG. Depending on the wind conditions. Not to shabby for a puffer. I have seen 99.5 MPG on my dic going down hill !!
I would suggest that you check your tire pressures. Recommended pressure is 44 PSI. I am running mine at 50 PSI. Not that much difference in the ride.
Also be sure to keep your car clean. The boundry layer on the little HHR's will add a tremendous amount of drag. Drag = less fuel mileage. Drive her hard the first 2000 Miles. Then drive it like you stold it. You , the engine and tranny will be happy campers.

When I came back from church today, Wheelie gave me a reading and 27.5 MPG, that is 4 MPG higher then when i did not reset my MPG!!:-D

Remember that the DIC is averaging mileage. So what you are showing now is over a much shorter period and with less variety of conditions. The longer you leave the DIC before setting, the more accurate the fuel economy will be.

For short duration, your best bet to get at the true fuel economy is to calculate it yourself.

My gas mileage is only 17 mpg that is in the city. Has 17000 on it mobil 1 oil and cgs intake red light to red light kills it. When it hit's the highway 23 mpg.

Strange to see such a wide range of numbers... I wonder if it is indicative of problems with certain cars, or if it is just the usual variance when mass producing cars...

Do we have a stats major or mechanical engineer here?;)

Driving style has a massive amount of impact. It is not necessarily any sort of problem that yields variety in fuel economy.