getting better mpg ('04 Aveo dropped from 41 to 32 mpg)

[delevanbluesman]

I have a 04 manuel 5 speed. When i first got this car i was getting 41 mpg. Now i'm only getting about 32.It has about 90k on it now.I'm wondering if its mass air flow sensor has anything to do with it's lower mpg. any input would be greatly welcome

[petrified.rabbit]

there are a lot of things that could cause this.. if a sensor was causing that much loss you should possibly have a check engine light.

have you ever done a tune up? changed the air filter? are your driving habits the same? do your timing belt?

how often do you check your mileage? just one time or consistently?

[delevanbluesman]

I did change the air filter, an i put in a containor of lucus injector cleaner.I will change spark plugs and wires next.my driving habits really have not changed.But could it be the mass air flow sensor ?

[petrified.rabbit]

it could be the mass air flow, but i bet its not. I am leaning toward you need a good tune up.

did you do the timing belt yet?

[delevanbluesman]

the timing belt is coming soon, next pay day

[MetroMPG]

How long have you had the car?

BTW, it's normal to see a significant drop in mileage in the winter compared to summer, even if everything is working properly.

I'd say 41 summer -> 32 winter is pretty normal unless your driving is mostly long highway trips (in which case you'd see less of a seasonal difference).

[tmot]

Wow, 32 is still pretty good, guess you do mostly highway driving? Here in sunny Singapore, 50% highway, 50% city, only getting about 29 mpg max so far on a 4-year old Aveo5 auto. Over here, we use km per litre, so it's about 12 km/l (or 9 L/km).

But my fuel efficiency did improve after I sent in for servicing, change engine oil, 24-point check, replace fan belt, etc. Before servicing, it was 24 mpg (10 km/l).

_________________________
tmot (Black '06 Aveo5 HB AT)

[delevanbluesman]

i've had the car 2 years in april. I drive mostly highway to work 30 miles one way. Even this past summer i notice my gas miles down some but i thought it was because i bought a new set of rims and they were 15" instead of the 14" that came with the car. But still i was getting around 36 mpg. Now i got studded snows on an that could cuase a drop in mpg.

[MetroMPG]

When you changed rims/tires, did you apply a correction factor to your MPG calcs to account for increased circumference? Your odometer is probably under-reporting distance travelled now, which would lower your MPG when you do the calcs compared to your old rims.

And yes, studded snow tires are going to hurt too

[delevanbluesman]

never thought about it! thanks