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What are the tubes attaching to the air box?

7.4K views 20 replies 6 participants last post by  Cr0ssF0cus  
#1 ·
So i am doing a custom sri, but i am lost on what all the additional things are attaching to the stock housing. The mafs is recogniseable, but there are 2 more tubes attached closer to the head of the unit. What do i do with them when all of that is removed? Do i need 2 breather filters? I just am not that mechanically inclined and cant find what i want online for info. Thanks in advance
 
#3 ·
=( would love to help but i have not worked on an engine like yours nor do i have the service manuals for that car i hope someone can help soon =/
 
#5 ·
usually how it goes xD..

i wanted to see if my engine was anything like yours and sadly its not or i would of gone out hours ago and checked
 
#7 ·
i have a 06 SAP its a 2.0 Dura but that corner looks NOTHING like yours
 
#8 ·
One is definitely the PCV system hose to the valve cover.

The second is more of a question, on some it's the air supply tube for the air pump. Doesn't look as likely here with the replaceable air filter, but I did hear of them being used on later model PZEV versions.

Current models it's hooked into the brake vacuum setup, hadn't heard of that on the MkII but it's possible.

Following them will def. help figure it out - which is which needs to be confirmed anyways.
 
#10 ·
PCV inlet hose attaches to the TOP of the engine, should see it at the back right corner looking from the front.

For the duratec that needs to attach to the new intake, since otherwise you are getting unmetered air into the intake from the PCV system. Zetecs take that into account, as stock they use unmetered air for PCV with a std. PCV valve controlling flow.

The other hose needs some more following, one branch at least may end up across the front of the bay and down to the RF corner of the car where an air pump if installed is located. If you look for the inlet pipe for that OVER the exhaust manifold it'll answer if yours is PZEV and has one.
 
#11 ·
zetecs dump into the airbox, its then pulled back into the intake through the maf
 
#12 ·
That's only during full throttle/low vacuum events.

Normal PCV flow is an intake through the valve cover (zetec from air box, duratec from inlet tube after MAF) then through the engine.

Exits through oil separator to PCV valve, then to intake manifold for both types. Intake vacuum helps the flow, not just from blow by/crankcase pulsations.
 
#15 ·
I assume you mean that the TB connecting boot is reused with the intake you have in mind. That's the case for most if not all, and with those other connections being made to the boot the question of what they do doesn't come up that often.

Deleting the PCV system is the most common reason to look at them, and there are arguments BEYOND maintaining emissions to leave that functional.
 
#21 ·
Spector makes a piece that has an adaptor for our MAF, that's what I had used. But went back to my modified intake box with a KN drop in. I change for the SRI when it is colder. I deleted the PCV line and have a rebreather on the valve cover and I run only the other vacuum line, I once ran with out both but I got a CEL for lean bank 2 I believe, or bank 1 cant remember