I just had a tune up done to the car..95 GXE....cause of the gas mileage poblem I was having...full tank load lasts about 260 miles....fricken piece of **** now eats up more after the tune up...car only last up to like 213-220 miles. I'm starting to think the o2 sensor is really ****ed up but the check engine lite is not on so wat else could be wrong with it?

 

Have you tried changing the air filter and checking your tire pressure?

 

Clean the throttle body, BG44k engine fuel system flush?

 

try checking the spark plug gap.
Don't go by what the box says about the gap being correct, get a gauge and check it yourself.

 

Either my car (03 max SE) has a problem with the gas mileage or it must suck gas like a hog compared to previous 2000 gxe. Gonna have that checked out.. I have to fill up the tank every 3 days, anyone have this prob?