KA24DE Emissions Removal FAQ

[BustedS13]

THIS IS A WORK IN PROGRESS, I WILL BE FILLING IN ALL GAPS. PLEASE DO NOT DELETE, THANK YOU!

I'm returning my s13 to the street, and in the process, am removing all emissions nonsense. Two reasons:
1.) Troubleshooting the KA, in my experience, is consistently a NIGHTMARE because of cracked/leaking vacuum lines.
2.) Emissions for OBD1 in my area consists of a visual for the carbon cannister, cat, and EGR piping, if they even bother to check. when my car goes in for inspection, it will have the shell of a cat bolted to a test pipe, and none of the other crap. we'll see what happens

While searching here I found a lot of information but had to do some digging. I'm putting all information here in this thread so that I can have a set of reference material, and so that others can benefit later. This will also, in time, contain my own experience. I will attempt to give credit for every quote i pull. Let's begin:

EGR

http://forums.nicoclub.com/zerothread?id=109345http://www.project-mayhem04.com/EGR%20Removal.html
pretty nice writeup concerning most of the intake mani, not just the EGR piping. recommends not disturbing the PCV. i beg to differ

some recommend replacing the EGR temp sensor with a resistor:

Originally Posted by SilviaSativa

The resistor is replacing the EGR Temp sensor. Cut the wires off the EGR temp sensor, solder one end of the resistor to one wire, repeat on the other end. I believe it is a 10k-ohm, 1/4 resistor

AIV (PAIR)

description

Pulsed Air Induction Reed Valve - for all intents and purposes, it's the smog pump. Its job is to introduce fresh air into the exhaust upstream of the cat/con during deceleration and extended periods of idle to help keep the cat "lit off" (at operational temperatures). The PAIRV disappeared from the engine in '94, with Nissan citing engine improvements being responsible for no longer needing it.

removal


PCV

description:

The PCV system is intended to
relieve the crankcase of any positive pressure by allowing it to vent through the free flow of air, either into or
out of the crankcase. Prior to advent of emissions, the crankcase was just vented through a breather on the
valve covers or intake manifold to the environment. Emissions requirements necessitated a “cleaner” way to
vent the crankcase to prevent the hot oil laden vapors from damaging air quality. That led to the inclusion of
today’s modern PCV systems. Current PCV systems are still pretty simple, consisting of an air inlet, a valve,
and an outlet. The air inlet (the vent tube) supplies filtered and metered airflow into the crankcase. The PCV
valve, which when opened by either internal intake manifold vacuum or positive crankcase pressure, vents
into the intake manifold, allowing the now oil contaminated but otherwise filtered and metered crankcase ventilation
airflow to be consumed by normal combustion processes.

removal:
http://www.ka-t.org/forums/viewtopic...er=asc&start=0
method removes more vac lines, plugging the intake mani holes.



carbon cannister

post removal issues

EGR

Originally Posted by BigVinnie

Yeah you got that right and the fact that exhaust gas no longer takes the space of air in the cylinder chamber during compression. It also completly FUCK's up the O2 signal.
That also means that it retards ignition timing so the engine technically will run like shit.
A retuned ecu will fix that problem by changing the A/R ratio. Or even a piggy back will work by fooling the MAF signal to the ecu that it is getting less air than it really has (somewhat correcting the problem by shrinking the pulse width of the injection in the cycle).
KA's run rich with there stock tune to begin with. The stock tune increases fuel richness by 7% more fuel than air at low rpms. Poor stock tune along with removal of smog equipment is one rich KA.

reasons to remove equipment

AIV (PAIR)

Originally Posted by nastjuid

The AIV (PAIR)... Was actually removed in the S14s because all they did was cause problems. The valve gets stuck open, and the sensor element in the MAF gets coated and you start having problems that don't diagnose a like MAF misread. Or something along those lines.

if anybody has anything to add, please do so!

[John_R]

Great thread. +1 for sticky

[frosti108]

gotta love emissions removal... i removed everything from my ka24e, and am in the process of doing the vg30e in my s12... all are a bit different, but have most of the same parts and systems. only thing i usually leave on is the part that has the idle screw lol

for valve cover breathers, best options are usually to either run it to atmosphere with a filter (easiest, works fine, but no vaccum) run it to the intake with a catch can (gets vaccum, minimal nastiness gets back in the intake) or if you have a welder, run it to the exhaust at an angle, with a check valve after the o2 sensor (like a drag car, takes advantage of a venturi effect in the exhaust, no worries of sludging up your intake)

i just run atmospheric breathers because im lazy

[de3zy]

good write up

[Devens240]

sticky thisssssss

[Fries]

+1 FOR DESTROYING OUR AIR! Cannot wait for this to be fully updated so I can join you in the War against Gore. AlGore that is.

[Oo_Skyline_oO]

I don't see the purpose of removing it in the first place..o_O if you're going to go through the trouble of all of this, might as well just replace all vacum hoses with new ones, and it feels great to have a car that runs clean and legit.

[surreybc]

http://forums.nicoclub.com/zerothread/254273

aiv faq

you will need the aiv for smog in british columbia. or anywhere that has idle test other than california. california has a different computer that keeps the o2 sensor in the loop during idle so you can get away without the aiv. aiv doesnt help smog reduction during driving.

[drift freaq]

Ya while its nice he is faq'ing all the emissions stuff it sucks he is removing it because it really does not take that much HP away from our engines. Go on polluting busteds13 I hope you choke on it.

[HS13KLS]

AHH THIS IS AWESOME!!!
i just did all of this though haha but im glad i know i did it right
+1 for you man

[Om1kron]

great post yet again!

[i8yourfwd]

great post, great info!

[twastheglow]

Does all that have to be removed or can I just block off the egr and deal with it's vacuum lines?
*mike*

[karl wasabi]

I have an EGR block off plate if anyone wants to remove their emissions. It's for a dual cam motor. PM me if you are interested.

Really good stuff...

[twastheglow]

I have what I need on the way. I just need to know if I have to remove all the other stuff. If I just cap that egr pipe and seal off any vacuum lines that need attention, wouldn't that suffice? Can't I leave the other stuff intact so my car will be drivable?
*mike*

[BustedS13]

Originally Posted by karl wasabi

I have an EGR block off plate if anyone wants to remove their emissions. It's for a dual cam motor. PM me if you are interested.

Really good stuff...

i blocked mine off by sandwiching a piece of license plate between the mani and a piece of the egr valve... i've never appreciated our hand-crank bench grinder as much as when i made that.

[Bigsyke]

I assume we should change spark plug heat range after removing the EGR system?"

[Matej]

Bump.

What is this?



The hose goes to the same thing as the EGR hose. Is it necessary, or can it be plugged?

Thanks for any info.

[93nismo]

when i put on my header last wek i cut the egr line and its currently plugged with a rubber hose and a big ass bolt(afro enginering at its best) anyway, when i take the egr system off, probly in a week or 2, were can i take it to get the ecu tuned? am i gunna have to go to a performance shop? or will most places do it. i only really ask because i kinda wonder if regular shops will bitch about the emissions removal or something and refuse to do it.

[Matej]

Came across this on KA-T.org.

Originally Posted by Corey

I am working on removing all the emissions garbage now so I labeled a few of the pictures in here to help me. Maybe it will help you guys too. Thank you to everyone who posted the original pictures.

color key:


Back of the engine:


Lower intake manifold:


Upper intake manifold:


key:
A: Exhaust Gas Recirculation (EGR) Outlet
B: Vacuum Hard Lines to PAIRC Solenoid Valves (Atmospheric and Vacuum) and Canister Vacuum
C: EGR Valve
D: EGR Control (EGRC)-Back Pressure Transducer (EGRC-BPT) Valve
E: Fuel Pressure Regulator
F: Swirl Control Valve (SCV)
G: SCV Control Solenoid Valve
H: EGR and Canister Control Solenoid Valve
I: Idle Air Adjusting (IAA) Unit (Idle Air Control Valve (IACV)-Auxilary Air Control (AAC) Valve, IACV-Fast Idle Control Device (FICD) Solenoid Valve, Idle Adjust Screw)
J: IACV-Air Regulator
K: Solenoid Valve Bracket
L: Heater Return Hose
M: IACV Line
N: Canister Purge Line
O: Collector Coolant Line
P: Positive Crankcase Ventilation (PCV) Lines


If I made any mistakes let me know please so I can fix it!

[Chad4061]

good info...gonna be removing my egr soon. might be doing the pcv delete as well

[projectRDM]

Originally Posted by Matej

Bump.

What is this?



The hose goes to the same thing as the EGR hose. Is it necessary, or can it be plugged?

Thanks for any info.

Just a vacuum line, usually branches off but it definitely feeds the FPR for certain. So make sure it's still connected. Whatever it ties into can be bypassed though.

[trigun808]

What Corey found, is that thread still alive? is there still pictures available?

[Likethunda]

The original post mentioned that the car would run like SH*t if the EGR was removed... because it would start running rich, and would need some kind of Retune

soo, why is everyone removing EGR again? and is this true^^^^^