A few months ago my friend helped me construct a DIY Cold air intake out of 2 inch diameter pvc piping with 2 45 degree couplers and a spectre cone filter. Since then I have been getting a lot worse gas mileage. When i say worse, i mean by 8-10. I just ordered and am waiting on an actual cold air intake, with a 3 inch diameter. Do you think that the DIY CAI was the problem? Or something else? roughly 2000 miles ago I changed my super worn out spark plugs, just not the wires. I think I might replace the o2 sensors when I have the money. Don't know if they have ever been changed, especially how worn down the spark plugs were. Any input or suggestions is helpful, thanks!

 

Did you make provisions for the lines coming off the stock intake?

 

A full tune up would probably be your best bet to gain back some MPG. Distributor cap, rotor, plugs and wires. You can also have your ignitor (ICM) and coil tested to make sure they are up to par as well.

What did the spark plugs look like when you pulled them? Could you describe them in terms a bit more descriptive than "super worn out". Where they white and chalky, black and wet or maybe light brown and dry? The condition of your spark plugs can tell you a lot about how your engine is performing and it's health.