So........ I've posted before regarding my poor gas mileage (2008 2LT 2.4 auto. 16k miles) and everything that everyone was coming up with was MAF sensor but it wasn't throwing any codes.
Finally I took it in for an oil & filter change (on special at local Chevy dealership for $21.00 total). I spoke to the service tech about the gas mileage and asked about the MAF sensor and, basically, he said everything that you guys did that if it wasn't throwing codes then no sense in wasting money by having it blown out.

NOW, here's the interesting part......I always check to see what my mpg is and, now, it's getting the mileage it SHOULD be getting. The service write-up shows that all they did was oil/filter change and full check of everything else with free tire rotation for $21.00. I know the car was purchased there new and serviced there as well by the previous owner and I told them if they do good and gain my trust then I will use them for future service. Just makes me wonder if they tweaked something, didn't charge me for it and didn't say anything..........

 

got me stumped, unless they did the old computer reset.

 

They had the car for about 45 minutes total while I waited for it - so I guess that's possible.....how would the computer reset affect gas mileage?

 

it resets all settings for the sensors to factory , drive it for awhile and see if it changes.

 

It's about the only thing that makes sense........

 

Hey Lawagz,
Good Lookin ride....
which dealership did you happen to go to? if not allowed to name, then what vicinity of town?
Z

 

It was a good report so I don't see why I couldn't name the dealership:

Freedom Chevrolet on I-10 just west of DeZavala Rd. in San Antonio

 

Yep, use them myself. Brian is great. Always treated very well.

 

Do they use a scan tool to reset the computer? My mileage is not what it used to be. I just attributed it to 100k miles and larger tires than stock.

 

Yes a scan tool is used to reset fuel trims. The computer has adaptive memory that adjusts fuel trims to make up for driving habits and sensor readings that may be a little off as they age.

Resetting the fuel trims may correct issues for a short time until the computer adapts to potential issues again if that is what was happing this time.

For now I would just monitor your fuel mileage and see what happens.