Hey there, I just bought a 3" aftermarket filter for my s13 zenki. I know it’s a very simple install, don’t need any help for that. But I saw somethings coming out the airbox I don’t know what they are and if they’re really useful. So just wanna be sure.
Looks like another sensor connecting to the MAF and some type of cubic box connecting with a rubber pipe directly in the airbox:
Close up of that other sensor thing:
So do I really need those things to make the engine work? Will it damage anything in any way if I unplug these and install the filter without plugging them back in any way?
how do i disable this EGR system? this thing is to reburn some emissions i guess? so it’s only for environmental purposes? if i leave the pipe next to the filter it’s gonna absorb those back in even if it’s not tighly fitted… sound funny, what do you mean? well i guess i could try it out, hehe… but what about the airtemp sensor? is it really useful? if i absolutely need it, how do i hook it back with the aftermarket filter?
ok, i just found out i should put a breather on the rubber pipe and hide it so cops can’t see it if they have to pull me over and check my engine. Thanks Gonad! I’ve never been pulled over for an engine checkup, but eh, don’t really want to risk it, hehe. Also, I wanted to know a detail about this EGR pipe. Does it sucks air in or blows it back in the airbox? Sorry for the stupid questions. I wasn’t expecting to deal with this, hehe.
As for the airtemp sensor tho, what can I do about this one? Do i really need to plug it back in some way, or doesn’t really matter if it’s not plugged back in?
What that does is when the car is at idle it takes fresh air and sends it to
the cat to keep it glowing instead of filling up with fuel and clogging up.
You can do one of two things. Remove the whole AIV system and join
together the Vac. Lines and just giver’ once and a while to keep things
flowing or like Brandon said put a little Breather filter on it.
The EGR is located behind the block inbetween the Firewall and the Head.
As for that sensor in the BOX thats the AIT sensor. You will need that, just
ziptie it as close as you can to the Intake Filter or do what I did and cut a
hole in your intake piping after the MAFS and insert it there.
alright! thanks ALOT for clarifying everything for me man! really appreciate it. So for the AIV, i’ll prolly do what Gonad told me and extend the hose somewhere where it’s not visible and install a breather on it. That way if cops pull me to check out my engine, they prolly won’t find it. Like I said i’ve never been pulled for that before, but can’t risk it. And for the AIT, i’ll prolly do what you said SHIFT_SR20DET. As long as it gets fresh air to read the right temperature right? If it reads too high, what will happen? Engine gonna stop?
I was planning to get a little 45° bent tube to attach the MAF on so it’ll face downward and forward as much as possible. Cause now if I attach the filter directly on the MAF, it faces toward the strut tower. Look kinda stupid anyway…
So thanks alot guys for the advices, I’ll let you know how it turns out.
Zack
I only need to find 2 more nuts for the screws and gotta buy that breather for the AIV pipe. Is it gonna be really loud if I don’t put a breather on it?
EGR system re-circulates expelled exhaust gasses on cold start up, it helps warm up the motor faster.
Correction
EGR does not re-circulate expelled gases on cold start up.
They re-circulate exhasut gases into the intake to lower combustion chamber temps, which will in turn reduce NOx.
Simply emissions related.
I’ve never been pulled over for an engine checkup, but eh, don’t really want to risk it, hehe. 
Also, I wanted to know a detail about this EGR pipe. Does it sucks air in or blows it back in the airbox? Sorry for the stupid questions. I wasn’t expecting to deal with this, hehe. 
So for the AIV, i’ll prolly do what Gonad told me and extend the hose somewhere where it’s not visible and install a breather on it. That way if cops pull me to check out my engine, they prolly won’t find it. Like I said i’ve never been pulled for that before, but can’t risk it. And for the AIT, i’ll prolly do what you said SHIFT_SR20DET. As long as it gets fresh air to read the right temperature right? If it reads too high, what will happen? Engine gonna stop?
