Focus Fanatics Forum banner

Replacing air box with K&N air filter. HELP

8K views 16 replies 13 participants last post by  kensaysrawr 
#1 ·
I am going to be replacing my zetec air box with a K&N filter for now. I know I will have to take out the air box and then replace it with the filter, but what do I do with the tube that goes from the air box to the engine.

The hose I am talking about is the hose that the number 4 is pointing to in this picture:


What should I do with it if I am just sticking a filter on?

HELP!
 
See less See more
1
#2 ·
Are you just replacing the filter element or a complete CAI system? I don't think you can just remove the airbox and put a cone filter on there. That little hose looks like a PCV hose, goes from valve cover to air box. You need this to be able to hook up somewhere on the airbox. If the kit was designed for your engine, then there will be a hook up somewhere, check the kit intstructions. Don't leave it off or plug it, your car won't like it.
 
#3 ·
That's the crank case breather hose that usually recirculates into the air box. Most people, including myself, put a crank case breather filter on the end. Here's my concoction:


I hear what your saying, it seems weird just slapping a filter on the end but essentially that's what I've done here but using a Volant tube instead.

You can pick those filters up at any parts store, I trimmed my hose down a bit
 
#8 ·
Btw I did the same as them, but I just left the lower box on. That way I still have the useless air snorkel on it as well as not having to bother with a breather valve filter
 
#9 ·
Not sure about the snorkel since I never tested it but I rerouted it using a velocity stack mounted in the lower grill. Used a 3" flexible exhaust pipe to extend it. I put just a low power fan in front of the stack and you can feel a good amount of air moving through and up just under the intake.
 
#10 ·
How has the K &N worked out for power and fuel mileage? Has anyone done the K & N on a 2007 2.0 pzev Duratec? My cars gas mileage has dropped about two mpg from last summer. Could the 'lifetime' engine air filter be the problem at 40,000 miles? tire air pressure, oil changes are kept up
 
#13 ·
I registered here because after MUCH google-ing I couldn't find a specific answer this SAME question pertaining to my Pontiac Vibe.

I just insalled a SRI on my car and when the crankshaft vent tube is plugged into my new intake, the engine stalls within 2 seconds of starting it. When left unplugged...I have a rough idle and a sporadic hissing noise, but it stays running fine and I got a pretty successful test drive. Then I tried plugging it and the idle is perfect and the car still runs great.

Is it ok to leave this plugged? or should I just put a little filter on it like what Mr. Bergner has done with his? Or is this expected with a Short Ram Intake while the MAF sensor adjusts to the new airflow?

Please pardon my ignorance, as this is my 1st venture into any kind of performance mod.
 
#14 ·
Posted via FF MobileCan`t see what kind of car, what SRI, or which hose you are plugging in where from here. General info - never plug a crankcase ventilation tube! Worst case, if it`s sealed REAL good is that engine seals blow out & you neeed a rebuild just to replace them...... Installed in the same order as stock, with hoses in the same relationship to filter, MAF, and throttle body as they were originally is best - other options defeat part of the emissions system, and except for some extreme race & turbo applications do NOT increase performance... Pulling the battery negative for a bit to reset the computer so it can learn the new setup quicker is recommended for any change that effects the breathing of the engine, even if a relatively minor change... Hope this helps, get back with more info/questions & the members here will try to help out....
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top