I purchased my 2004 Chevy Malibu Classic in January of this year. When i first started driving it, i was getting about 29 mpg (80% highway, 20% city). I was quite happy, expecially considering my driving style. Well, Now its October, and I'm getting 24MPG. I do my oil changes Every 3,000 miles (+/- 100 miles), and the filter as well. I use Mobil 1 Full-Synthetic. I installed a K&N filter at 27,000 miles. I now have 43,xxx miles. I was thinking possibly fuel filter. Any other ideas?
Check your tire pressures. Clean your air filter. If that doesn't help, try a new set of spark plugs.
I'd put my bet on the fuel filter.....it can really hurt your mpg.
Ive changed mine twice and I have a little over 50,000 miles on my ecotec and getting usually 30+mpg with an auto.
Later
Redrider02
"i reject your reality and substitute my own." -adam savage "mythbusters"
I will give that a try. Air Psi is always maintained. Im a big supporter of correct Air pressure. I hate it when I tell people they had they're tires overinflated, and they say "well, the tire says 44 psi". Really gets to me.
exhaust? header? intake manifold? intake? acetone added to fuel? larger tires?
will be noisier, might also have warranty issues....i cant seem to get a straight answer out of GM on what voids the warranty and what doesnt, mechanics say different things on different days of the week, salesmen think that you can do whatever you want as long as there is no forced induction, and the parts guys dont know a cam from a header.
actually while i am here, does anyone have a number to call to find out what voids the warranty and what doesnt. dealership folk are @!#$ clowns.
Dont drive over 73 MPH highway keep your RPM's below 3000 the lower the better, if its cold outside your mileage will drop 2-3 MPG and dont due heavy acceleration, passing... be conservative. Even though you can get 30+ MPG highway under quick accelerations your getting below 19 MPG.
With a big car like that even though you can get 29-32 MPG highway (My wife has the intrique 215HP (31 MPG hwy) it still get 19 MPG city. Any city driving will KILL your gas mileage because 19 MPG sucks.
Also remember that the fuel changes in the winter and that will cost you 1-2 MPG. The government says you dont loose mileage but I drive 120 a day to work and believe me in the winter you loose from temperature, the garbage they make to clean up the air.
They say winter fuel puts out less pollution but since you get poorer mileage you have to burn more fuel to go the same distance. So in "reality" your paying more money for a scam.
this may sound odd, but bigger tires also help (without overdoing it of course). keeping the engine clean works....fuel filter, air filter, regular oil changes.
i have heard stories about these aftermarket filters improving fuel economy but i have also heard stories about them not being able to actually filter as well as the OEM.
exhaust can have a positive effect.
throttle body, and header is a little questionable, potentially they could i guess but i would be careful before getting a new one cause they get expensive.
tire pressure helps, always.
acetone to fuel?!?! i have heard about this only once, it is apparently supposed to have dramatic effects on fuel economy, but when throwing anything into your gas tank, you are taking a risk. if something goes wrong (too much or too little) you can kiss another piece of your warranty goodbye
flushing your lines may help too
rpm low is another one, feel the engine, if its struggling then you probably arent doing much good. i have heard good things in between the 2k and 3k mark on these engines, you drive a bigger car so it might be higher (assuming you drive a car with a manual transmission).
there is a tech service number on a lot of your gm documentation, but the bottom line is that to void a warranty you have to do damage to your car by adding on a part, and the dealership has to proove it without a doubt that it caused the fault.
