I just installed a K&N cone filter on my Zetec. What I did was simple and very cost effective so far and I'd like some opinions on why I should add more expense to an intake system.
I removed the stock air box and filter and clamped the lip of the cone filter over the cylinder of MAF sensor (the portion that used to stick inside of the airbox). I also added a small filter to the PCV tube. It isn't supported in a rock solid manner so I will be building a small box from sheet aluminum to mimick the FocusSport sheild but I'm not worried about it the way it is.
I don't think it makes any significant performance gains, but it sounds great for a 4cylinder.
This seems to have made a dramatic drop in MPG. I'm through more than 1/2 tank and I'm 30 miles off my normal pathetic pace of 23MPG. I was hoping for 26-30 when I bought the car, what gives?
DO NOT gauge your MPG by "half a tank". The Focus gas gauge does not read steady- as in, some parts of the tank, it drops faster than others.
Go fill it up, and set the trip odometer. Then, drive for a while, then when you fill it back up, see how much it takes to fill it, and divide miles driven by gas used. Don't try to guess what you're getting, it'll end up way off.
You should've actually increased MPG by using a cone filter.
ProjectFocusFast wrote: DO NOT gauge your MPG by "half a tank". The Focus gas gauge does not read steady- as in, some parts of the tank, it drops faster than others.
Go fill it up, and set the trip odometer. Then, drive for a while, then when you fill it back up, see how much it takes to fill it, and divide miles driven by gas used. Don't try to guess what you're getting, it'll end up way off.
You should've actually increased MPG by using a cone filter.
Exactly! You just cannot use your gas gage to compute mileage. When I fill up, I always, "top off." This means I can actually see the gas stay in the filler neck. It takes a little longer, & you have to use a deft hand on the pump. From the time the pump automatically shuts off, I can get 1. 2- 2 additional gallons in. I then drive about 300 mi. before getting gas again. When I do, I try to go to the same station & use the same pump as I did before, and top off. Then do the math.
FWIW, I have a lightly to moderately modded ZX3 5spd, and I average 32-35 mpg in summer and 29-32 in winter here in northern Ohio.
One more tip...don't drive around all day in 2nd gear!
____________________ If you can't read this, you're illiterate.
I would normally agree but I'd confidently bet anyone my next paycheck that the mileage is significantly lower on the first tank than the past 6 (I've checked mileage at every fill-up and it's always been a steady 23MPG +/- .5). I'm a hair above "E" right now and I've got 189 miles on the trip gauge. I'll be filling it up again today and I'll let you know the findings. By citing the gauge, I was just ballparking as this is the first vehicle I've ever had that gave me pretty darned close to 60 miles per 1/4 tank on the gauge.
Fear not, I'm new to the Focus but there is nothing that I have not done to a vehicle from rebuilding Fiat 4cylinders to Ford 460s to a full frame-off restoration (rebuilding for off roading). I know better than to judge mileage by a gage, it was just obvious from the first 1/4 tank that it had gotten worse.
The problem could be this:
You put the filter right in the enmd of the MAF, which may cause it to send false signals. The Focus MAF counts turbulance (sp?)) in the air to determine how much air is coming in. With the filter being right on the end of the MAF, it may be creating extra turbulance, making the ECU think you're taking in more air than you actually are, therefore decreasing your gas mileage.
My reccomended fix:
Find an exhaust shop that specializes in diesel exhaust. Get a 6" section of 3-1/2" pipe from them. Go to the hardware store and get a rubber PVC boot for 3" PVC (it will be 3-1/2" I.D.) Slap the filter on one end of the pipe (after you clean the pipe out, of course!) and put the PVC boot on the other end, and strap it to the MAF. This will put some space in between the filter and MAF, possibly fixing your issue.
Also, reset your engine computer (take the neg. batt. cable off, hold the brake for 20 secs (to drain the capacitors) and then put the cable back on. Drive as usual.
Most people say yes. I say it really doesn't matter, because the car will "learn" it's modifications eventually anyway, but it can't hurt. For the 1 minute it takes to do, you might as well.
