Gas Mileage

I have a 96 accord with your basic upgrades such as CAintake, exhaust, ect.... The problem is that I have been squeezing almost 400 miles out of a tank of gas, and now I am only getting around 250 miles a tank I dont know whats going on. Checked for leaks...NONE I did recently switch to synthetic oil, but that was it. Help.

check spark plugs, dist. cap, dist. rotor, and ignition wires. from my understanding and from i've heard...when you change your intake to cold/ram air intake...your intake manifold pulls in more air. in turn the computer compensates that by adjusting more fuel. correct me if im wrong. however...going from 400 to 250...don't think your intake would cause that drastic of a change unless you got a lead foot. i would check the items above to make sure they are up to par to burn the fuel properly. good luck.

Yeah, check your plugs, wires, fuel filter. Make sure you are running correct air pressure in your tires, and that your brakes aren't rubbing. Also be wary of your driving habits...perhaps with the new sound/feel of your newly modded car you maybe driving it a little faster/harder than normal...

Did you have to modify or plug any items to use the cold air intake? Some aren't set up right to make correct use of MAF, PCV, etc.

Take a look at the O2 sensor, make sure it isn't coated with soot, which will keep it from working right and affect mileage. If it's black and sooty, the engine is running too rich, and is not working with your mods correctly.

Thanks guys for the input. I did have the fuel filter changed about a month ago, thinking that it would solve the problem, but it didnt. I am currently running ngk plugs and 9.3mm wires, both are less than 3 months old. I am going to check the O2 sensor first thing tommorow, by the way I didnt plug anything else in with the CAintake.

How would I adjust the richness verses the leanes of my fuel?