I recently took a 5,000 mile trip with my 805T just after installing a new Pureolator air filter. I was transporting two mountain bikes on a roof rack which I understand will reduce gas mileage.

Prior to the trip my average mpg was at 26.2 and would increase to ~26.6 on a trip. During the 5K trip with the bikes my mileage dropped to 22.2 mpg. At first I blamed it on the bikes and was thinking that I could have rented bikes for less than the cost of transporting them.

After I got back and resumed my normal driving pattern (without the roof rack) my mileage did not increase, as expected, but decreased. Suspecting the filter, since it was the only thing I changed, I removed it and replaced it with a piece of cloth (temporary). The next day my average mileage started to increase and returned to the normal average of ~26mpg.

I never thought a filter could have this much affect on mileage. I have a K&N on order to see what effect it has. I have heard that they are the BEST. I know it is the most expensive. I also noticed that the car was not it's normal "peppy" self on this trip.

Has anyone noticed this much decrease/increase in gas mileage after changing air filters?

Thanks for feedback,