trouble passimg smog on your KA? Look here

[singlecamslam]

So the most common issue with passing smog on a ka24de is NOx being too high. Even if you have a good cat you can still fail due to high nox. High NO is due to high combustion temperature and that is usually control by with the egr.

My problem was my EGR was fine AND clean and working properly, so WTF. So here is what you do:

Before cleaing
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03769.jpgSee this little allen key nut? Its a 10mm. Its on the intake manifold right about the throttle body.
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03760.jpgOpen that up and it leads all the way back to the EGR. What happends is those holes get clogged and the EGR cant allow air back into the engine. So here is what you do
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03763.jpgGet a long pipe cleaner like thing
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03764.jpgShove it in there in a thrusting motion
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03765.jpg
and this is what your plug should look like
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03762.jpgThere is also a plug on each runnerhttp://i200.photobucket.com/albums/aa37/oldskool916/DSC03761.jpgThose should also be cleaned.

End result
http://i200.photobucket.com/albums/aa37/oldskool916/DSC03770.jpgBAM

[driftnuts]

perfect thanks i have a very good feeling thats whats wrong with my egr setup

[S-Nation S13]

good info...

[fakts13]

i wonder if using some seafoam would help making the scrubbing unnecessary... or at least make it easier to dislodge the carbon...

[joshchewuhh]

exactly what i need! was your throwing a CEL?

code 32 or no?

[sked707]

Good stuff! Got smog coming up so this is now on my to do list

[1on1]

I will do this once I replace my egr solenoid...

[Jonnie Fraz]

Thanks for the info. I will do this before I run mine down for smog.

[yaba94070]

what where the co2 #'s after that

[SmallTownDrifter]

Thanks man I'll do that tomorrow

[sincity_sil80]

i'll check that out.. im in the process of installing my egr so this worked out perfectly.

[dued]

I went to Lowes today and couldn't find a big pipe cleaner like the one pictured in post #1, where did you get yours?

[matts13vert]

Awesome info this is the most common reason these cars dont pass smog! code 32 is a headache...

[dued]

What tools did you use to get the plug off? I used a 3/8" 10mm hex socket with a 3/8" breaker bar, and I couldn't squeeze it into the small space required. I also tried a huge 10mm allen key & the combo of both of these tools resulted in a stripped plug :wan:


So now I have a stripped plug that is still on my intake manifold & I can't clean it.






































































One more time. :wan:

[SmallTownDrifter]

should I try to clean the tube that goes from the headerd to the egr

[singlecamslam]

ok that pipe cleaner is actually an oven cleaner, not sure where you get them, but i actually found it.

In order to get that plug off, you have to take the throttle body off, and upper hose out of the way along with throttle cable and stuff. Than i used a 10mm allen key with a breaker bar and used my entire body to break it lose, its really in there.

[562s13]

do the sohc's have those as well?

[dued]

ok that pipe cleaner is actually an oven cleaner, not sure where you get them, but i actually found it.

In order to get that plug off, you have to take the throttle body off, and upper hose out of the way along with throttle cable and stuff. Than i used a 10mm allen key with a breaker bar and used my entire body to break it lose, its really in there.



Thank you very much!

[sbkcrew44]

do the sohc's have those as well?
Yes they do.

You can also find something similar called an dryer vent brush or something like that at home depot.its not exactly the same, but close, and its the best alternative i could find at the hardware store.
It looks like this http://www.homedepot.com/catalog/productImages/300/71/7193355c-047e-4f14-92d4-04f5a909fbe8_300.jpg

[dued]

Bump. Tips from my experience - The bolt plug strips easily, so be careful. Also, my mechanic is using some sort upper engine manifold cleaner spray stuff to soak the manifold overnight, then he's going to use a gun barrel brush to clean out the port. Should help the process for those of you who can't find a dryer vent / oven brush thing.

[okinawadrifter]

I used a piece of hard wire almost like a coat hanger wire. I shoved it throught all the runners and then used my wifes vacuum cleaner attachment to suck out all the broken up stuff out. It was all caked up in there, even thought my EGR was clean. I guess after 20 years it would be clogged up. And yes first initial smog I failed, after scrapping everthing out went for smog and passed with flying colors, amazing what cleaning of the intake runners will do.:aw:

[yetijeff]

was this causing you to throw a code 32? ive changed almost every component in my egr system and its still throwing a code. im single cam tho does it have the same cleanouts?

[sked707]

Anybody try this on an sohc yet?? I was looking at mine and it looks like a pain in the ass to get the bolt off, theres a little pipe in the way there. :bash:

[sbkcrew44]

I did it on a soch. There is an identical bolt on the back, take that off and you can get to it from the back if you have a flexible handle on the pipe brush.

[darkslide92]

damn hella helpfull, my symptoms were same as yours egr and cat brand new but was still reading 800ppm @15mph.

thanks for the info

[Seriously]

Damn that sucks i looked at this after i failed ...

[dkim1985]

Damn that sucks i looked at this after i failed ...

...same here. i failed my test last night. looks like im gonna be doing some cleaning tonight. lol

how long does this take to do? is there any liquid cleaner that I can use instead?
i failed my NO by only about 40 points..

[dkim1985]

i bought this Dryer Vent Brush at 'Bed Bath and Beyond' for $10;
Casabella® Bendable Dryer Vent Brush - Bed Bath & Beyond (http://www.bedbathandbeyond.com/product.asp?SKU=13600520)

..and did all the instructions posted except for the individual runners because i didn't have the right size allen key(?). didn't know the runners had different size allen key nuts than the 10mm..anyways..hope it doesnt matter too much.
the 10mm allen key nut is REALLY on there..no joke. i used the short end of the allen key and put a metal pipe over the long end for leverage to loosen the nut.
after shoving the vent brush in and out multiple times..i stuck a small hose inside as far as i could that was connected to an air pump. gave it a few good pumps to blow out any little particles that was just hanging around in there.
looking inside the hole, it still looked a little dirty but definitely WAYYY better than it did before..so just reinstalled everything and put everything back the way it was. started the engine up sooner after..and you can tell it's running a little cleaner.

a few notes for people looking to do this method;
-do NOT do this process when your engine is running hot. this may be stupid but i feel as though it should be mentioned for safety reasons. let your engine cool down before you do this(cool down as in OFF for awhile). the headers that you're going to be working around will be hot as well as the radiator and especially the coolant since its going to spill.
-newbs(like me); at least wear disposable gloves when doing this cause u're gonna get sh*t all over your hands..go to your local auto store and u'll find a box of disposable gloves. easy.
-u have to pull out the hose that connects your radiator coolant so have a pan or something underneath otherwise u're gonna have coolant all over the ground.

i'll be going for my 2nd smog check later today..will keep everyone posted with the results~
im pretty sure im going to pass because i was only 40 points off the passing score..lol

EDIT:
..didn't pass. got gross polluter instead. loll
im going to go the carb cleaner route.

[ASheng89]

I tried this today with some carb cleaner and now my car won't idle, any ideas as to why? When I started the car after this procedure, it idled okay for maybe 3 minutes or so, and then it suddenly started sputtering and oscillating until after a while it just stalled out. After the first time it stalled, the idle was never really steady and it smelled like my car was running rich. The engine stalls out every time now, either immediately after starting or a minute or two after.

I actually managed to get the plug off and clean the passageway with some kind of trumpet cleaner brush thing my friend gave me without removing the intake or the coolant hose. I only had to remove the bolts holding the throttle cable in place and kind of set it off to the side. I'm pretty sure I reinstalled everything correctly...

Any help would be appreciated, thanks in advance.

[zerodameaon]

I wish that was what would help me. Fixed my egr system before my smog and i had NO numbers of like 9 and 3. Mine was high HC.

[dkim1985]

[just updating everyone from my last post]

i took the smog test a week later for a 3rd time and passed.

after the 2nd test, i seafoamed the intake system through the throttle body and poured a bottle of Chevron Fuel System Cleaner with 91 octane and drove the car for a week. when my tank was 1/4 left i took the smog test again and passed 9 points below the California max. (max=559, result=550)
..yes i know..its stupid how close it was..but whatever, it worked. lol

NOTE:
after you clean the intake runners with that brush, i would recommend to seafoarm the intake system like I did. cleans everything out.
and then drive the car around for a few days with the fuel system cleaner (only costs like $5-$10, i used Chevrons Techron $7.99 at autozone.).
before you go get the smog check, drive on the freeway for atleast 30 mins (pushing it/redline etc isnt necessary..just drive it normally).

To ASheng89;
Yes your car is going to smell like its running rich because u broke up all the carb deposits and its being pushed out of your exhaust system. If you spray carb cleaner into your intake, you have to wait for it to dry before your start it up again otherwise your engine isn't gonig to take in much 'oxygen'..which is probably why your engine won't idle smoothly.
Again, try using seafoam through the throttle body with the engine running and at about 3k rpm so the throttle will suck it in. You'll see smoke coming out of the exhaust which means its working. do that for about 5 mins and hopefully it'll clear most of the carbon out.
feel free to ask any questions..

[singlecamslam]

I wish that was what would help me. Fixed my egr system before my smog and i had NO numbers of like 9 and 3. Mine was high HC.



If your NO number are that low you can put E85 in your tank (like 15 - 20% mix) and it will lower your HC but raise your NO.

[zerodameaon]

If your NO number are that low you can put E85 in your tank (like 15 - 20% mix) and it will lower your HC but raise your NO.
That low of number just seems crazy to me but hey its a supposedly calibrated smog machine so whatever. Im really close to passing HC so i think with some tweaking I will pass.

[dontxploitme]

Are you guys paying for every test? I need a shop in SoCal near ontario that doesn't charge if you fail and that is low friendly

[singlecamslam]

its usually 20 if you fail with a free retest, and 55 if you pass.

[Edwin562]

i tried this and Seafoamed my engine, and it passed with flying colors... thanks for the write up

[zerodameaon]

So i fix all the problems stated on my first smog test and go in for a retest. I failed worse then with all the shit fed up.

[singlecamslam]

high HC is most likely the cat, you might be running really rich thats why your NO numbers are so low. Trust me when i say i feel your pain, i've been smogging (or trying to smog) 240sx's since 2002, and they are retarded. My record was failing about 5 times, keep your head up it WILL pass eventually.

I vote make a thread ALL ABOUT SMOG, where we help our california members with the ever loathing smog test. What do you think?

[zerodameaon]

^Agreed, the smog threads are to spaced out.

I found an interesting issue yesterday that i am curious if it would affect my smog. My throttle was bent. The bar that the throttle cable rotates and the plate is attached to was bent in such a way that it only allowed the throttle to open half way. I will figure her out eventually or run over California's minimum $ amount for a waiver.

[dkim1985]

So i fix all the problems stated on my first smog test and go in for a retest. I failed worse then with all the shit fed up.
What was the time frame in between those 2 tests?
same thing happened to me but thats because i didnt drive the car around enough after cleaning it so the 2nd smog test caught all the NOx.
i decided to drive the car for a week after cleaning it again with seafoam and retested with a 1/4 tank left.

[FRpilot]

I vote make a thread ALL ABOUT SMOG, where we help our california members with the ever loathing smog test. What do you think?

this.. a sticky faq on top would be great. my registration expires august 2011. i have smog due and its throwing a code 55. i have no idea what i am going to do.

[zerodameaon]

What was the time frame in between those 2 tests?
same thing happened to me but thats because i didnt drive the car around enough after cleaning it so the 2nd smog test caught all the NOx.
i decided to drive the car for a week after cleaning it again with seafoam and retested with a 1/4 tank left.
Time frame was about 2 weeks. I seafoamed her last week and im looking to go back in this week. Really interested if the bent throttle had anything to do with it.

[Live2Slide]

this.. a sticky faq on top would be great. my registration expires august 2011. i have smog due and its throwing a code 55. i have no idea what i am going to do.

Lmao dude i think code 55 means there's nothing wrong with your car lol

[zerodameaon]

Lmao dude i think code 55 means there's nothing wrong with your car lol
Theres always that saying "A little too quiet"

[FRpilot]

Lmao dude i think code 55 means there's nothing wrong with your car lol

exactly why i thought it was a stupid code.


Theres always that saying "A little too quiet"

are you saying my engine is going to blow up :(

because i do kind of have that feeling since its making a ton of weird noises.

also even though code 55 states there is nothing wrong with the engine, in my mind, it translates to THERE IS SOMETHING SERIOUSLY WRONG WITH YOUR ENGINE which is why lately, every time i am driving i have no confidence.

[s13 @ fullboost]

hell ya I did the same exact thing 23rd=gross polluter 25th= clean vehicle hahah the smog tech was like you failed yesterday you already fixed it? haha I also put octane booster in the gas tank it helps alot.

[zerodameaon]

the stated above weird noises are most likely timing chain related.
I changed my ECT and my gas mileage went from 17 to 27. I think ill pass now. I did pass 2 weeks ago on a pretest with no warm up so.

[zerodameaon]

So my friends car passed with a SR (tech willing to look the other way during visual.) His numbers were higher for his car but yet we both own the same car with two years difference, both came with KA24DEs, except mine was a auto at the time of my testes and his has always been a manual. I guess what Im asking is did my numbers go up now that I'm swapped over to 5spd or is there really that much difference in two years.

[wangan_cruiser]

i just took my smog test yesterday and it fail because of high nox. i stumble on this thread, im trying to find the allen nut but i cant find it. anyone wants to show me where it is? the pics dont work no more. thanks

NO max : 493
my NO : 609

[dkim1985]

i just took my smog test yesterday and it fail because of high nox. i stumble on this thread, im trying to find the allen nut but i cant find it. anyone wants to show me where it is? the pics dont work no more. thanks

NO max : 493
my NO : 609

err..i'll try to take a picture later tonight but..you have to move the intake 'tube' to access it. its right above the throttle body on the intake manifold i believe..
i would just use seafoam..that sh*t works wonders. thats how i passed smog.
used chevron's fuel system cleaner into the gas tank and used seafoam through the throttle body for a few minutes to clean the intake system.
and then drive it on an open freeway for about 30 mins and u should be good.

[darkslide92]

right behind the upper radiator hose. it's kind of a bitch to clean out without disconnecting the hose, but it can be done
29927

29928

[darkslide92]

okay i have a question for those who have used the seafoam. I have Mopar engine degreaser. supposedly a little stronger than seafoam, and i was just wondering if you guys changed your oil after running the seafoam or not.

thanks

[darkslide92]

err..i'll try to take a picture later tonight but..you have to move the intake 'tube' to access it. its right above the throttle body on the intake manifold i believe..
i would just use seafoam..that sh*t works wonders. thats how i passed smog.
used chevron's fuel system cleaner into the gas tank and used seafoam through the throttle body for a few minutes to clean the intake system.
and then drive it on an open freeway for about 30 mins and u should be good.

^^ What were your NoX readings before you seafoamed your car, i'm just curious to how low my numbers will drop. i'm currently getting 1550ppm @15mph on stock timing but if i fully retard it, it reads 850ppm.
thanks for any info

[wangan_cruiser]

^^ What were your NoX readings before you seafoamed your car, i'm just curious to how low my numbers will drop. i'm currently getting 1550ppm @15mph on stock timing but if i fully retard it, it reads 850ppm.
thanks for any info

holy shit thats high. i was already tripping out when mine was reading 609 (ppm) compare to the max 493

ill post pics i just cleaned mine. i didnt have to pull out the throttle body and upper rad hose. all i did was unbolt throttle cable and use that 10mm allen nut with a pipe for more leverage to break it loose. use that brush singlecamslam mentioned and soaked it with a carb cleaner.

[singlecamslam]

Sorry guys i was cleaning my photobucket account and accidentally erased all the pictures. The ideal way is to take off the manifold and get it hot tanked or something, but thats way too much work. Theres some really good ideas people have in this thread. Smog your cars the legal way!

[darkslide92]

I actually cleaned those runners quite recently maybe month and a half two months ago and they were quite clean. I just took off the other smog stuff

[darkslide92]

on the drivers side next to the brake master cylinder leading towards the air box. I'm going to carb clean it and then pater see if I can remove the pipe that leads from egr to exhaust manifold and then clean it out with the same brush mentioned earlier if possible. And then spray the mOlaf stuff in the throttle body

[wangan_cruiser]

so i just cleaned mine and there is a noticeable difference on idle and acceleration. took the car out for a quick spirited driving and my car run smoother than before. now going to have use some cleaner and run it through this week and ill take my smog again. will be posting an update about it.


so heres my fair share of these thread. took pics for everybody who has having problem with high nox.on the pics my intake was off but it was unnecessary. i thought i was able to sneak in between the upper rad hose and use a 3/8 10 mm allen wrench but i was wrong.

just take off 2 10mm nuts (green circle) and remove the throttle cable bracket so itll give you some space for the 90 degrees 10mm allen wrench to get in and slowly move the upper rad and you will be able to loosen the 10mm allen nut (red circle)
http://i585.photobucket.com/albums/ss295/wangan_cruiser/10allennut10mmnut.jpg

the carbon build up
http://i585.photobucket.com/albums/ss295/wangan_cruiser/carbonbuildup.jpg

the brush i used
http://i585.photobucket.com/albums/ss295/wangan_cruiser/thebrush.jpg

behind the 10 allen nut
http://i585.photobucket.com/albums/ss295/wangan_cruiser/10allennut.jpg

i used a carb cleaner from walmart cost me $1.97 per can. soaked it overnight then scrubbed it with the brush i used. gotta remember if you soak the intake runners your car wont start until you dry it out. so dont freak out that thinking you did something wrong.

ill post more pics for the sohc, ill be doing it again because my wife's sohc needs smog for next month. to the op thanks!

[andisan]

^^^ thanks buddy, i need to do this to my KA before i take it in for smog on tuesday, thanks for the pics too, and the how to write up. I've been afraid to do these all due to the removal of the radiator hose, I've done it one two many times, and dont want to do it again, but ill do it that way you did it, Thanks again.

[niteridaz503]

LOL thought i was the only one with damn issues with smog, I haven't tried cleaning that area above the throttle body but even after cleaning EGR system, replacing o2, full tune up, replacing fans(one was dead), seafoaming the ish out my coupe and i still have failed 3 times.

One question though, my exhaust system is as follows: 2 1/2 yr old cat, 2 1/2" piping to a resonator & 3'' all the way out no muffler im thinking this is also posing a problem as im thinking its too free flowing.

[Thethrash]

Hey guys so i have been trying to smog my 91 240 (dohc)
it passed everything except the nox(common thing with 240s)
so i cleaned the egr valve and the metal pipe that goes around form the exhaust manifold to the air manifold.
My nox was reading 3300. and i was wondering if that's possible, perhaps i hooked the egr back on wrong?
can some one please help me :/

[darkslide92]

Did you check to see if the egr works? Squeeze it and see if it dies/stalls

[S-Nation S13]

Damn smog gremlins chasing me again..

15 mph
HC 61/64 FAIL BY 3 CO 0.52/0.07 NO 493/847 FAIL WTF

25 mph
HC 47/41 CO 0.50/0.05 NO 516/952 FAIL WTF

I replaced my egr 2 years ago along with the egr solenoid and the egr BPT .. I cleaned the passage way to the egr via the 10mm hex bolt sea foam the engine except running it crank case I only did gas and intake ??? What else should I do???

[S-Nation S13]

No one ? Insight ?.

[hassanbakar123]

is the timing right? what was the CO2 at?

[koenig]

get a little under half a tank of gas in your car, then put in like half a gallon of denatured alcohol in the tank, and take smog again.

Makes your shit CLEAN but then as soon as you leave, go fill up your tank and drive nicely

[S-Nation S13]

Timing is at 18 btdc co2 is at 15 mph 14.2 25 mph 14.3

[upsdude]

awww what happened to the pics :(

[S-Nation S13]

Anyone..this is pissing me off..I'm pretty sure I have a clogged erg pipe into the exhaust mani..but and things else ?? Will sea foam reach that pipe ???

[niteridaz503]

Anyone..this is pissing me off..I'm pretty sure I have a clogged erg pipe into the exhaust mani..but and things else ?? Will sea foam reach that pipe ???

Try removing it i did & soaked it in gasoline or something strong and run a long wire brush through it thats what i did, Seafoam helps too but seafoam at your own risk

taken from another forum
\/

Seafoam ( Pros and Cons) : General Chat (http://forums.nicoclub.com/seafoam-pros-and-cons-t86360.html)

[S-Nation S13]

Since my hc were off by 3 and only on low speed..is it safe to say that my ignition system is good enough..just a little more cleaning ...and since my co where hella low is it safe to say my cat is ok ??? Nox I know primarily has to deal with egr..so I'm assuming I have a clogged egr pipe..bc if my egr was to be completely broken my nox would be at a stupid level ..

[S-Nation S13]

http://240edge.com/manuals/91-94_240sx/ec.pdf

Dc-32
Page EF&EC 107

Any clues

[S-Nation S13]

Checked egr function there is a vacuum source, and the egr valve does move while at 2000 rpm and closes at idle...slapped a brand new o2 sensor just for the hell of it..my question is is it vital or should i just do it ..that I clean out the egr tube to the exhaust manifold?

[Thethrash]

I just passed my emissions today. my problem was my egr wasn't on completely,clean your pipe with wd40 and your valve. I put 5 gallons of 91 oct. and alcohol set my timing all the way to lean. Passed flying colors. and my nox before was reading 3300.

[S-Nation S13]

How where you able to remove your egr ??? I'm trying to reach the metal tube to the exhaust manifold ??

[S-Nation S13]

Able to remove the egr with the egr tube today..my plan is to spray into the egr tube with carb cleaner..and into the holes they hook up to.. Can I spray into the egr as well ?? My egr is in working condition , that means the egr bpt and egr solenoid is working as well..so I'm thinking a good clean will lower my nox..

Any other tips or cleaning I should do please lemme know ..

[S-Nation S13]

All finished up ..brand new everything..lol gonna run some chevron cleaner and 91 octane..I'll keep you guys posted ..

[Thethrash]

My no ppm was 3346 (15mph) and 2948 ppm (25mph)
i cleaned my egr valve and bpt, set timing all the way to lean.
91 oct + alcohol. made sure all the vacuum lines where sealed for the egr.
passed with 0008 ppm on (15mph) 0004 ppm (25mph).

[S-Nation S13]

I passed !!!

Shit so close though all numbers were 1 off the max allowed!!! Time for a new cat !!!

[kingkilburn]

So I just attempted this and FUCK THAT PLUG. Why the fuck is there an aluminum plug in an aluminum manifold? Now I have to drill it out and get a huge extractor in there and hope the threads survive. At least the plug is like $3 and Nissan still stocks it.

[kingkilburn]

Nox at 3000+ HC slightly high @15mph
Nox around 1200 HC fine @25mph

No cel. EGR works. Cat and o2 sensor replaced. Vacuum lines all new. Passage behind plug cleaned.

[niteridaz503]

how long ago were the cat & O2 changed? did you heat up the cat nice & pipin hot as well?

[kingkilburn]

O2 last year. Cat about 4 months ago and it was hot.

[deadlydragon72]

hey i know this is an old post but its exactly what need to try and i was hoping you might still have the pics and be able to reset them or just send them too me it would be much appreciated!!!!! thanks!