Alright, ever since I installed my K&N CAI installed, I've seen a decrease in my gas mileage every time I fill up. Tonight when I filled it, I've lost almost 3 mpg over the last several months. I've checked my tire pressure and they were a little low but nowhere near where they'd need to be to drop my gas mileage as much as it has. Could the CAI be a part of the problem? Any ideas on what could be causing it?s

 

It could be that the K&N is just causing your maf to read funny. Did you remove the screen or perform any other mods when you installed it?

Also did you reset the computer after you installed the K&N?

To reset the computer, disconnect the negative battery terminal, hold your foot on the brake pedal for about 30seconds to discharge any juice in capacitors anywhere. I'd let it set another 3-4 minutes and then hook it back up.

 

My wife's Sport Trac and my '93 Conv. have both decreased in gas mileage the last couple of weeks. Both are down about 2 mpg. less than what they were averaging.

 

That seems odd 'cause I thought CAI's were supposed to improve fuel economy from more air being introduced to the engine but then again I'm a sucker for clever marketing...
Maybe your spark plugs are going bad and its just a coincidence?
Maybe you like the new found horsepower and you're in the throttle a bit more and don't realize it?
If nothing else pump your tires up to about 80psi and see if that helps. (don't actually do that, but last week a guy with a corvette came in the shop with 2 blown tires because of that)

 

haha. Whats the difference between a Corvette and a porcupine?



With a porcupine the ****** on the outside.

 

I think they are putting alittle more water into the gas pumps b/c my car has also lost a few mpg...

I used to get about 130 miles on a half tank now I'm barely getting 100.

 

Hey I drive a v6 and yes i too have noticed about a 2 mile per gallon loss on mine as well. :notnice: i thought it was just because of my new wheels and tires, but now i am thinking differently. just thought i would add my .02

 

Some gas has ethenol blended into it. MPG sucks with that stuff. Summer blends in huge metro areas have that stuff in it. Its FALL now so maybe the good stuff is back in their tanks.

 

I would go the route that maybe the Computer just never relearned the new air/fuel mixture. I'd go with what Scott said above and give that a try.

 

Maybe you are testing the increased performance of the CAI too much?


On my 1999 GT I used to get about 280-300 miles on a tank of gas

 

Hey thanks guys...I'll try and reset the computer again to see if that helps. I did take out the screen on the CAI when I installed the K&N so maybe a reset is all it will take.

 

I've seen mixed results when removing the MAF screen. If your mpg is getting that bad, put the screen back in. It helps even out the air flow and keep any turbulance to a minimum.

 

Is there anyway to tell if the computer reset itself? I would have thought my radio presets would have disappeared but they came right back on and I left the terminals off for quite a while.

 

It shouldnt.. also your radio shoudl have lost its presets. Make sure you press the brake pedal down for about 30seconds.

 

I didn't lose my presets, though. I had the battery disconnected for (at one point) close to 20 minutes and I had the brake pedal down for at least 30 seconds probably close to one minute. Presets stayed though. I did notice that my tripometer reset itself.

 

Stock Radio, or after market? Some after market radios have a "battery" backup (sometimes battery, sometimes flash memeory).

If its stock, it really should have reset.

 

it's stock MACH

 

I've had the same trouble with a CAI on a Honda. Switch back to OEM,