Only getting 20 MPG! What's wrong?

[Werm9]

My grand am has a 13 gallon tank and i can only manage 250 miles on it. 270-280 miles on a great tank, but for the most part its pretty stable at 250 miles on a tank. I DO NOT drive hard at all. I did put in a cold air intake back in summer, could that be why my gas milage is so horrible for a 4cyl 2.4L engine? its winter here and for the past 3 weeks temps have been ranging from -5 below to 25 F. Does the combination of a CAI and very low temps effect my gas milage that bad?

[Madcat455]

2.4L is only rated at 22/30 to begin with, and if you're driving mostly city then your not that far out of line.

Next.. if that pic in your sig. line is your intake, then it's not a CAI. all you did was remove the restrictive factory air box and put on a less restrictive air filter. It still gets the warm engine compartment air.

TRUE CAI's will have the air filter or air intake located outside the engine bay (usually in the lower part of the LF fender), to draw in colder air outside of the heated engine compartment.

also... putting on less restrictive intake and exhaust componets actually hurt gas milage. When you allow the engine more air, it has to compensate with more gas to maintain the factory preset Air to Fuel ratio. Also, colder winter air will also cause lower gas milage for that same reason. The ECM has to make up for the Denser air charge the engine is getting (even though the air is comming from the engine compartment, it's still colder than what it was in the summer... just not as cold as the outside air)

So... If you're driving mostly city, and with that air filter... then I'd say you're right in line with where you're supposed to be.


If you're doing mostly Highway, then you've got a different problem... as even with that filter you should be getting at least 26. And then I'd be checking my Plugs, wires, Air pressure in the tires, Fuel filter... etc. Basically give it a good tune up to see if that's it. After that, it gets really involved.