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Emissions test - to pass or not to pass?

4035 Views 15 Replies 8 Participants Last post by  BShark
I have to do the e-test in 1.5 hours, first time with a KLZE.

Fresh KLZE (swap finished in mid-August), already running synthetic oil, 94 octane fuel, all O2 sensors are new, 2 year old hi-flow catalytic converter, replaced a faulty EVAP purge solenoid, but no EGR hooked up. Throwing a CEL, most likely for idle control, which stays off for the first 20 minutes after I uplug the battery to reset the ECU, so I'll have to do that immediately before the test.

Nervous that it won't pass...need it to pass to be able to renew my registration, which I already got $110 ticket for having it expired.

Will post the results later tonight.
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Bad news - fail

So here's the results:

4 out of 5 areas I passed with amazing numbers -- why is the NOppm so bad? What should I look to first? Would the 'guaranteed to pass' stuff help me with this?
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I was reading through this thread:

...and first, is the NO ppm reading on my test the same as NOx? If so, should I do what was suggested in the other thread to retard timing, keep ten & grd jumped & try the 'Guaranteed to Pass?' Even though the OP in that thread still failed, I have a feeling he was just a lil too daft to know what he was doing...
I believe NO is nitrogen oxide (not to be mistaken for N20, nitrous oxide); hence the layman NOx... beyond that, I'm not sure I can contribute much. I know Matt made comment about having adjusted the fuel-air ratio lean to get his beast to pass last year; I recall he also mentioned that some people resort to running alcohol in order to pass the test (but evidently wasn't necessary for him).
Found this link that might have some useful suggestions... - All About Everything: How to pass your Drive Clean test

Also found a link suggesting that the EGR is critical for getting the NO down...
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I don't have much to contribute bro...looks like lack of egr is the culprit. I just went through all this last week, but luckily no ze in my car.
Egr will help it pass, retarding the timing will help, pulling the t-stat will do the trick, making it run a little rich will probably do it too. Could even be that your plugs are the wrong temp range. Also, what octane are you running? Higher octane will lower NOx.
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I'm running 94 octane. Can't attach EGR tube, blocked off. The plugs I'm running are one step colder than stock, if i recall correctly
Spark plugs

After reading this thread last year:

I have been using NGK Iridium BKR6IX11 plugs (post #24) which are supposed to be the stock plugs for the KLZE engine, since they are shorter and a step colder (than stock KLDE ZFR5F-11 plugs) to accomodate for the higher compression.

The plugs that came out of the KLZE engine we put in in August are: ZFR6FGP, the '6' instead of the '5' in the klde stock plug representing one step colder.


I dropped in the 'Guaranteed to Pass' stuff yesterday, have to run the full tank before I can test again.

I have an AFPR -- So you're saying if I should turn up the pressure on that to run rich (I run at 45psi now)? Wouldn't the fumes of more fuel in the exhaust cause the readings to be worse? How does this work?
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I was looking at a wiki page on o2 sensors, and it said that running lean can cause high nox numbers, so if you can find a way to introduce more fuel into the mixture, it should help the issue. I don't know if upping the psi on the afpr will help, maybe someone else can chime in.
Run a full tank of ethenol and "FTP' , that should work. Synthetic oil helps too.
Wouldn't you advance the timing (if you could) retarded makes worse emmisions.
NOx levels are directly controlled by the egr valve. the egr recirculates exhaust back into the cylinders reducing the combustion temperatures...the higher the temps the more NOx is produced. (the reason its called NOx is because there are different oxides of nitrogen NO NO2 etc)

anyways, without an egr there is an almost certain chance that you will not be able to get the NOx levels low enough to pass....sorry man

funny DE with an egr (that doesn't really work) failed waaaaay worse than that on the NOx lol
So, here's a few things I read online... As with any internet info, questionable at best, but hey, we're clutching at straws here now.

Ethanol Fuels | Energy Development Initiative | Science, Technology, Energy and Mines | Province of Manitoba
(see the paragraph that starts "The downside of gasohol...")

"The downside of gasohol use can be increased emissions of nitrogen oxides (NOx)" ... "The degree to which emissions increase depends on the vehicle and emission control technology used."

General Information on Vehicle Emissions Reduction -
(see section "ii. Ethanol")

"The auto/oil study concluded that there was a statistically significant increase in NOx of about 5% with the addition of 10% ethanol."

Call me nuts, but the only 94 octane I know of in Ontario is Sunoco's ethanol blend. What percent ethanol is it? Perhaps running the normal 91 might increase your HC and CO a smidge, but bring the NO in line? I mean, doing so would require retiming, but still.

Also, failing that, or in addition to that, you can retard your timing; I think this also reduces NO while raising the other readings though, so be careful as you do so. You're more than welcome to borrow my timing light anytime, just give me a call to make sure I'm home.

Oh, and one last thing, get rid of that CEL. As I understand, doesn't your computer "re-learn" it's air/fuel ratios whenever you reset the CPU? If this is true, maybe you're buggering yourself with the last minute code reset. I never reset my CPU within a week of E-test day, I set my timing and everything the week before and get a good few days of driving on it first. So if at all possible, I'd really try to diagnose that CEL code first. Unless it's the EGR bypass one, I guess that'd be problematic.
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I think Kevin's right...if you're resetting the code using a scanner, it should be okay, but if you're resetting by disconnecting the battery, then I've read that you will get higher readings until the ecu has gone through a few cycles.
Did you pass the test? If so, what worked?
loL, no, not yet. With my stupid back luck, I adopted a 2000rpm idle 2 days before I was going to do the etest. :mad:

But I got a reference from someone to go do it a local performance shop who understands the deal with these JDM engine swaps and will most likely make accomodations, so that's the path I plan on taking once I figure out this idle issue :D
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