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-   -   HiGH NOx smog test need any help to pass!! (#/f/showthread.php?t=262439)

S-Nation S13 07-09-2009 07:01 AM

nope as per FSM timing is 20' btdc with +/- 2' look on page 29 under the EF & EC

dennydizzo 07-09-2009 06:55 PM

ok so instead of taking out my egr and cleaning it i got another catalytic converter and hooked it to my car and took it to a smog shop(a no pass no pay place) to see how the new numbers will look...turns out i still failed due to high nox at both speeds only went down about 200..

so after avoiding removing and cleaning my egr looks like i have to..and ive read that retarding the timing will reduce NOx numbers..this is correct? and how much can i lower it without damage..

BlazedGlory 07-09-2009 07:17 PM

Sorry to be a smartass, buy why ask for help if you don't want to hear any solutions? I still say check out the EGR system. It may not be that the valve itself is clogged, it may just not be operating at all. Who knows. That would still be the best place to start unless you want to keep throwing parts at the problem. If it is all good, at least that will be eliminated from the very good possibility list.

dennydizzo 07-09-2009 08:15 PM

Quote:

Originally Posted by BlazedGlory (Post 2906239)
Sorry to be a smartass, buy why ask for help if you don't want to hear any solutions? I still say check out the EGR system. It may not be that the valve itself is clogged, it may just not be operating at all. Who knows. That would still be the best place to start unless you want to keep throwing parts at the problem. If it is all good, at least that will be eliminated from the very good possibility list.


oh no doubt im going to take apart my egr..i just wanted to rule out the catalytic since its easier to remove than the egr..but now im just wondering if retarding the timing will help me out lowering the NOx level along with cleaning or replacing the egr..

BustedS13 07-10-2009 04:11 PM

when my state still had emissions testing, i once unplugged an injector and let them run it on three cylinders to pass with flying colors.

dennydizzo 07-11-2009 04:35 PM

Quote:

Originally Posted by BustedS13 (Post 2907817)
when my state still had emissions testing, i once unplugged an injector and let them run it on three cylinders to pass with flying colors.


r u serious?will that actually work?

BustedS13 07-12-2009 01:38 AM

Quote:

Originally Posted by dennydizzo (Post 2909322)
r u serious?will that actually work?

it worked for me.

dennydizzo 07-17-2009 09:11 PM

okay so i ended up taking apart my egr and cleaned the hell outta it..it was filled with alot of black carbon crap and i ended up buying a brand spanking new catalytic converter and changed my o2 sensor..my results were:

15mph
HC.....max=88.....measured 30
cO.....max=0.52...measured 0.03
NO.....max=704....measured 27

25mph
HC.....max=53.....measured 16
CO.....max=0.50...measured 0.04
NO.....max=738....measured 5

finally passed with Flyin colors...thanks everyone for their suggestions and output!! :bigok:

S-Nation S13 07-17-2009 11:13 PM

lol thats whats up ..but i think you could of passed with out the new cat but anyways its something that you dont have to replace down the road..hehe

BlazedGlory 07-18-2009 04:45 AM

Agreed =P. Well, he'll have to replace it down the road when it fails again =P

dennydizzo 07-18-2009 07:54 PM

Quote:

Originally Posted by BlazedGlory (Post 2921359)
Agreed =P. Well, he'll have to replace it down the road when it fails again =P

:mepoke:iF...iF it fails!!

BlazedGlory 07-19-2009 05:29 AM

=P All I'm saying is if you had to replace it once you will have to again. Everything fails at some point. That is why I'm so gungho about diagnosing problems. If you replace something that hasn't yet failed you miss out on some of its usable life and the new part will fail at some point as well.

handinpants 07-20-2009 02:10 AM

Your nox levels are high because something in your setup is causing it to run lean and therefore increasing the combustion temps, also you want to fill up 91 octane, maybe buy a new cat and clean the egr, or you can write down the cost for all this, and compare it to paying for a dirty smog and go for the cheaper of the two.

But I recommend you go the legal route

Seikenman 07-31-2009 11:25 PM

Congrats on passing your emissions test. About your knock sensor code. You were getting it because you were running 87 regular gas. The dohc 240's need to run 91. You can run 87 but the sensor will detect knock, throwing the knock code, and retard the timing

BustedS13 08-01-2009 03:02 AM

ha ha ha. i capped off my EGR with a chunk of license plate, and i'm about to get an exhaust fabbed up from the header back with no cat.

god i love not dealing with bullshit

miklos 09-09-2009 03:59 AM

Timing at 15 is the factory setting

modulation 10-11-2009 08:52 PM

I'd bet you had a pre-cat exhaust leak.
I had similar problems (really high nox, low hydrocarbons.)

Turned out to be a exhaust leak right before my cat.

miklos 10-22-2009 05:25 AM

I pulled out my egr after running seafoam through the throttle body and found carbon caked inside the manifold.
My egr solenoid had no ground and the vacuum hoses were melted back there on an SOHC.

miklos 11-09-2009 12:00 AM

Failed again 3x
 
I just failed for the 3rd time.
After the 2nd time:
I replaced the spark plugs and plug wires, O2, EGR solenoid, cleaned out the EGR ports, 2 new fuel injectors, new vacuum hoses, and the MAF.

15mph NOX 2803
25mph NOX 1276
15mph CO .87

Do you think a new cat would fix all of this?

s13silvia123 11-09-2009 12:06 AM

change your motor oil helps reduce nox. new oil helps the motor work less and creates less nox.

where i use to live use to have smogging and i failed on NOX so i changed my motor oil and went back and passed with flying colors.

miklos 11-09-2009 05:22 PM

Oil was changed 5 weeks ago. I'm sure the Cat must be bad causing the NOx to be high

DreamN 11-09-2009 05:25 PM

Are you getting any codes at all? How's your idle?

Typically when a cat is bad all three areas are higher than normal.

miklos 11-09-2009 07:20 PM

I was getting a code for the EGR temp sensor but the light has been off for a week. Idle is good.

http://thechive.com/wp-content/uploa...-poster-16.jpg

NismOkatFreaK 11-23-2009 08:38 PM

Damn smog suck's, I kept failing so I figured it had to be the air idle control valve or whatever that things called that everyone takes out. So I took the pipe off that attaches to the exhaust, put a nickle in there then reattached the pipe and walla, I passed! Just thought id share what I had to do.

DreamN 11-23-2009 09:00 PM

You blocked off the EGR pipe? lol

240trooper 11-24-2009 02:29 PM

my 240 years ago didnt pass for shit. found out the cat was gutted lol . New cat and had teh egr replaced and it passed. failed was GP over 3000's , passed in the 110's

miklos 11-24-2009 04:49 PM

Quote:

Originally Posted by NismOkatFreaK (Post 3149385)
Damn smog suck's, I kept failing so I figured it had to be the air idle control valve or whatever that things called that everyone takes out. So I took the pipe off that attaches to the exhaust, put a nickle in there then reattached the pipe and walla, I passed! Just thought id share what I had to do.

You mean the hose at the bottom of the AIV going to the exhaust?

Almedarj 11-24-2009 08:19 PM

i gotta friend who will just pass your car even if you failed already but it cost about $300 not bad considering you might pay to get what you thought was the issue fixxed and have your car fail again lol

ILLES13 11-24-2009 08:24 PM

Quote:

Originally Posted by krissynbeau (Post 2868140)
I just had the same problem. I had the egr line cleaned out and had to buy a new cat. I just passed yesterday


Same here, i have the same year same motor coupe. also hit NOX in the 3000's.
bought a brand new catalytics converter, passed it like a champ

miklos 11-25-2009 08:17 PM

I know a new cat will make the car pass.......but Gold Shield gives them out last after they do everything else. And since I'm running rich---the cat would go out in 3 months.........so I might as well fix the richness and stop wasting gas.


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