I drive a little Cavalier that had been getting about 29 MPG over the summer, and dropped to 27ish over the winter. I just took a trip to NC last weekend, and I got 29 MPG on the tank of gas I got in MD. I filled up again in southern VA (maybe South Hill?). That tank got me all the way to Winston-Salem, and back to near the NC/VA line I think. I got 35 MPG on that tank! I just filled up this morning, so it was most of the trip back and back and forth to work this week, and it's back to 31 MPG. I realize that highway driving is best, but my "town" driving isn't even really town driving. :lol: The trip to work is about 25 miles, with no lights and only 1 stop sign. The rest of the time I'm cruising on 301. I just don't know why my normal MPG is 27-28 lately, but it gets up to 35. Is the gas better outside of MD?

Check the pressure in your tires. If you run them on the high side of the range listed on the sidewall, you 'll get better miliage.
Harder tires = less resistance to rolling = better mpg

Check the pressure in your tires. If you run them on the high side of the range listed on the sidewall, you 'll get better miliage.
Harder tires = less resistance to rolling = better mpg

Ok, but I didn't add air to my tires on the trip. Do you think there could be a difference in the quality of gas?

Ok, but I didn't add air to my tires on the trip. Do you think there could be a difference in the quality of gas?

Outside temperatures affect tire pressure. :yay:

I burn diesel in my car and I know there is a difference between winter and summer diesel. My mileage always drops during the winter. Don't know if there are different additives in the winter that may change you mileage.

Different areas may have different blends/additives depending on region and time of year. It's possible you got a batch that gave you better mileage.

I know at the peak of the gas pricing, fuel I got at both Sunoco and Sheetz (93 octane) was causing my truck to ping. It was not the same as we got before, and are getting now. I can run 89 octane with no pings now.

Outside temperatures affect tire pressure. :yay:

:yeahthat: My tire pressure sensors come on when it's cold out. They go off after I've driven for 10 minutes or so.

Tire pressure varies about 1psi per each 10 degrees of temp. Dont know that we've had that big a difference between us and SC to make a real difference, especially given that once you drive about 10 miles, your tires are heated up enough that the pressure in the tire is the same if outside temps are within 15-20 degrees of each other.

I suspect the gas. As noted, different areas get different blends, and some places get different blends based on the season.

:yeahthat: My tire pressure sensors come on when it's cold out. They go off after I've driven for 10 minutes or so.

Your tires should be set to the specified pressure when cold, me, in October, I set them that way, then adjust again in spring. If your light is on before you drive, even after the light goes out, your still under inflated, which will affect your handling and mileage. The light is set to alert you to a dangerously low pressure, not manufacturer spec. My car, for instance recommends 32psi, but my low light doesn't come on until 28psi.

CG, do you normally get gas that contains alcohol? And did you happen to notice if the fuel you got out-of-state had alcohol blend? That could def account for the variance if yo got non-alcohol blended fuel.

CG, do you normally get gas that contains alcohol? And did you happen to notice if the fuel you got out-of-state had alcohol blend? That could def account for the variance if yo got non-alcohol blended fuel.

I didn't pay attention. :ohwell: Maybe that tank from South Hill didn't have it. :shrug:

I really don't think it was the tire pressure, because the temp difference wasn't that much from MD to NC.

Your tires should be set to the specified pressure when cold, me, in October, I set them that way, then adjust again in spring. If your light is on before you drive, even after the light goes out, your still under inflated, which will affect your handling and mileage. The light is set to alert you to a dangerously low pressure, not manufacturer spec. My car, for instance recommends 32psi, but my low light doesn't come on until 28psi.

Jeez, I don't know much about that. My DH checks it for me all the time b/c the light comes on fairly often in cold temps and the pressure is always good.

I have 2 separate warnings, one for 'Tire Pressure Low' and one "WARNING: Tire Pressure Extremely Low" or something similar. I've had the 2nd one come on once and my tire WAS low, but anytime it's been the 1st warning, they've been fine.

My uncle has an Expedition as well and he has the same problem. I hate it b/c when the warning comes on I am expecting it to go off after a few miles. It's as if I don't know whether to take the warning seriously or not :lol: Though I always have someone check just incase.

Thanks for the info.

I didn't pay attention. :ohwell: Maybe that tank from South Hill didn't have it. :shrug:

I really don't think it was the tire pressure, because the temp difference wasn't that much from MD to NC.
Ethanol blended fuel cuts MPG by 10% I believe I read back when the ethanol craze started to take off.

Ethanol blended fuel cuts MPG by 10% I believe I read back when the ethanol craze started to take off.

:yeahthat:

Depends on the system ,and when he checks. If you drive even 3-4 miles, your pressure reading is going to be artificially high. Your tires heart up as you drive, and gain psi. From my house to work, about 7 miles, my tires go from 36-39/40psi. My car lets me see each tires pressure real time on my dash.

To be accurate, it needs to be checked before driving the car at all, or make an allowance of that effect. If the only time its going off is in the AM, before driving, its about %99 sure your tires are not at the right pressure cold.

I see a lot of pumps that say "contains up to 10% ethanol", so I assume that gives them the lattitude for each fillup to have 0% to 10% ethanol. So you'll never know how much energy per gallon you really have. Adding to that is "winter gas" often contains "oxegenates" and I have no idea what states/counties/etc have that, and when the cutover dates are (which might vary by location". I assume that St. Mary's doesn't have oxegenates because they don't have emissions testing. But I would guess those variables alone could account for 10% or so change in MPG.

The dearth of sun spot activity is helping your MPG. yw

Could it just be simple highway vs. city mileage? I know when we go on trip our MPG increased drastically b/c we aren't doing all the start and stopping – I mean like 5-7 MPG difference.

Could it just be simple highway vs. city mileage? I know when we go on trip our MPG increased drastically b/c we aren't doing all the start and stopping – I mean like 5-7 MPG difference.

Possibly, but my "city" driving is very rural...not at all like St. Mary's.

Possibly, but my "city" driving is very rural...not at all like St. Mary's.

:yeahthat: :livesinthesticks:

:lol:

:yeahthat: :livesinthesticks:

:lol:

:lol: Yep.