When I first got my car about 4 months ago I was getting 18 mpg on average. On the highway about 25. Now for some reason the mpg reads 15 on average. How accurate is this computer? Can I reset it to give me more accurate readings? I was thinking of getting some STP fuel system cleaner and a K and N filter. Are these right to buy? Though I have a v6 this can't be right. I was thinking of getting an oil change, but I still have 1,500 miles left on my old one. It's 3,000 miles or how many months before an oil change? Thanks a lot. I gotta fix this!

 

i never rely on the computer readout, i use the trip odometer and use the amount of fuel i pump into the car to get the real mileage.

i wouldn't bother with the fuel cleaner. you can put it a k&n filter, although i don't think it will do much. make sure you let the oil dry before putting it in.

you can change your oil now, i wouldn't worry about the time lapse between oil changes. what's the worse that can happen? you spent extra money on keeping your car running properly. fwiw, i change my oil everytime after going to the track even if i've only put 500-1000km since the last oil change.

you can also try changing spark plugs and checking tire pressure.

 

awesome... thanks a lot dsq I will be sure to do all of these things and let you know how she runs!

 

if you will reset the computer you will not have better readings, you will have worse, any computer will show a close to reality result after 3000-4000km after a reset