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Crash
03-10-2009, 04:47 PM
I need to lower the NOx on the mighty 3FE in the '88 62. HC and CO pass but the standards for NOx have been lowered by nearly 50% in the last two years. Numbers on the truck are the same as they were two years ago but the new standards are busting his chops. Doesn't seem right that standards can get stricter on a truck that has always passed emissions before. Any help on lowering his NOx will be appreciated.

wesintl
03-10-2009, 04:59 PM
I feel your pain.. I had to get rid of my camry due to the stricter emissions.

Crash
03-10-2009, 05:01 PM
I feel your pain.. I had to get rid of my camry due to the stricter emissions.

Drastic and not the way I will go with trusty steed Bart. I'll get a PO box in a non-"enhanced" emission testing area before selling my favorite Cruiser. If worse comes to worse, I'll move to New Mexico! Viva la no testing!!! Really, how can standards for a 20 year old vehicle suddenly be cut in half? They are legislating my truck off the road and it sure as hell puts out fewer pollutants than some I see on the road these days. Every time I pass the testing station at 6th Ave and I-25 the sign says the "health" of my vehicle is "Good". I guess I need to drive by the remote trucks more often where I can control my foot on the throttle better than the testers at the emission centers seem to be able to.

timmbuck2
03-10-2009, 06:17 PM
interesting to hear more...my friend just bought a 88 FJ62...think she might have trouble passing?

Crash
03-10-2009, 06:35 PM
Doesn't make any difference what I think, now does it? :D

Chris
03-10-2009, 07:47 PM
Sorry to hear this Steve, I'll be in the same boat when my time comes around I suppose. :(

baileyfj40
03-10-2009, 07:50 PM
somtimes its nice to have friends in HIGH places. Not in the front range counties.

Later

jettaglxdriver
03-10-2009, 07:51 PM
Thank God I "still live in El Paso County"

thefatkid
03-10-2009, 08:46 PM
I would check to make sure you have proper EGR function. To little flow can raise the NOx levels as the EGR introduces inert gas into the combustion chamber "cooling" the combustion due to less to burn.

I would back the timing down a little. Retard the timing, the point of combustion will occur after TDC keeping cylinder pressure lower, that reduces heat.

If the first 2 don't work replace the catalyst. This is not cheap and I'm sure you would need new cats every emission time.

Our latest governor decided to clean Colorado up by making the standards very strict and upping the dollar amount for the fix it voucher. I think we are at the Cali/CARB standards now for older vehicles. Not a fair test to make vehicles pass at standards that are more strict then the original federal standards.

Beater
03-11-2009, 06:51 AM
I have seen MANY a flanged cat in my day if you get my drift. bolts not allowed to rust and all that... fresh cats around a certain time of year, with an old stale one hanging around the rest of the year does wonders...

MDH33
03-11-2009, 07:42 AM
Did you run the fuel tank to almost empty and add some Heet? Always a good practice before emissions. I believe it's supposed to help all of your numbers. It did on my 60 that only runs on 5 cylinders. :)

DaveInDenver
03-11-2009, 08:03 AM
Did you run the fuel tank to almost empty and add some Heet? Always a good practice before emissions. I believe it's supposed to help all of your numbers. It did on my 60 that only runs on 5 cylinders. :)
This might or might not work, depending on what the useless emissions nazis are doing to the pass numbers. The testing people understand and know the relationship between all the components, so they are changing the pass/fail criteria to eliminate the chance to sneak by using these tricks.

HEET is just alcohol, which lowers NOx by reducing combustion temps a little. That works when the other measurements are not particularly low because if you lower the combustion temp you reduce combustion efficiency. That will make the byproduct numbers go up, usually HC will see the biggest increase when trying the HEET trick. So if you only fail NOx and the other numbers have a lot of margin, then a couple of bottles might do the trick. But if the HC and CO numbers are close as well, then this trick might help you pass NOx at the expense of failing the other parts. The more sure solution is to retard the ignition a little, do a tune-up (could use slightly cooler plugs), run known good catalytic converters and maybe tighten the valve lash.

Bart's 3FE is running high compression, which is very much of a problem for NOx, as are hotter cams and in general anything that makes your truck more fun to own and drive. It's a pretty clear relationship, higher compression generally = higher NOx production. Stupid government, how they can stand there and expect a car to pass tighter requirements than it was made to originally is pure bull****.

SteveH
03-11-2009, 09:00 AM
My brother's '93 FZJ wouldn't pass in Denver until he retarded the timing even more (than the first time) and added 1.5 gallons of E-85 to 7ish gallons in the gas tank. I think his failed on Carbon Monoxide. E-85 is a very cheap way to add alcohol, as opposed to many bottles of HEET.

leiniesred
03-11-2009, 09:42 AM
Just went through this (high NOx after they CHANGED THE RULES) with my Father-in-laws V8 Vortec powered Jeep TJ-8.

We messed around a bunch with A/F ratios tuning. while it does run even better now, we wound up putting on a much bigger catalytic converter and it finally passed.

Crash
03-11-2009, 10:23 AM
Just went through this (high NOx after they CHANGED THE RULES) with my Father-in-laws V8 Vortec powered Jeep TJ-8.

We messed around a bunch with A/F ratios tuning. while it does run even better now, we wound up putting on a much bigger catalytic converter and it finally passed.

Yeah, the exhaust has an aftermarket cat on it and I'm hearing more and more that they don't hold up very long. All other systems, EGR, ignition, AFM are tested and good with the AFM getting some adjustments in addition to a 50/50 mix of 91 and 100 octane gas that it didn't have for the first test. Timing was a little advanced over stock for the test and is now back to stock and I might retard a little further for the next test. Thanks for the suggestions and help. I'll report back when Bart passes the test.

Chris
03-11-2009, 10:26 AM
Every time I pass the testing station at 6th Ave and I-25 the sign says the "health" of my vehicle is "Good". I guess I need to drive by the remote trucks more often where I can control my foot on the throttle better than the testers at the emission centers seem to be able to.

Do the road side tests bypass the need to go the the inspection stations?

Uncle Ben
03-11-2009, 10:35 AM
Yeah, the exhaust has an aftermarket cat on it and I'm hearing more and more that they don't hold up very long. All other systems, EGR, ignition, AFM are tested and good with the AFM getting some adjustments in addition to a 50/50 mix of 91 and 100 octane gas that it didn't have for the first test. Timing was a little advanced over stock for the test and is now back to stock and I might retard a little further for the next test. Thanks for the suggestions and help. I'll report back when Bart passes the test.


The cat I put on Ricecake this last time seems to be the shiznit! After burning out several aftermarket cats I seem to have one worthy of the heat my right foot seems to generate. BTW it was Bud himself that talked me into spending a few more $'s and go with the spun cat....

Spun Metallic Cat Converter (http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE-59959&N=700+4294923429+4294838974+400636+115&autoview=sku)

Crash
03-11-2009, 10:42 AM
Do the road side tests bypass the need to go the the inspection stations?

I drive by the RapidScan trucks all the time and still get the notice that I have to go to the testing station. I think the guys in the trucks just sit there and drink coffee or whatever. :lmao: I do make sure that I am either going a steady speed or decellerating when going by the trucks but no luck so far with any of our vehicles with bypassing a test at the station.
Uncle Ben, you'll get me to go to Bud's yet, won't you? ;) Thanks for the cat tip as it may just be required.

DaveInDenver
03-11-2009, 10:47 AM
I drive by the RapidScan trucks all the time and still get the notice that I have to go to the testing station.
What's the story on those? We always get the testing notice, too. If the benevolent emissions overlords accept your rapid dealio you are not sent an emissions test notice? Maybe it's because I tailgate and in hopes they never get my license plates... That's S.O.P. for me, to try and obscure my front plate by squeezing in nice and close to the car in front of me so that photo radar, intersection cameras and all that can't see it. Or at least that's what I'm hoping. I hate big brother surveillance. I also always flip them the bird just in case some jackboot does actually see it.

Uncle Ben
03-11-2009, 10:49 AM
What's the story on those? We always get the testing notice, too. If the benevolent emissions overlords accept your rapid dealio you are not sent an emissions test notice?

Correct! When you get your plate renewal notice it will state "No Emission Test Required" I have been exempt from test twice now and I hopefully will get the same news in a couple weeks when the post card should come.

Uncle Ben
03-11-2009, 10:52 AM
I drive by the RapidScan trucks all the time and still get the notice that I have to go to the testing station. I think the guys in the trucks just sit there and drink coffee or whatever. :lmao: I do make sure that I am either going a steady speed or decellerating when going by the trucks but no luck so far with any of our vehicles with bypassing a test at the station.
Uncle Ben, you'll get me to go to Bud's yet, won't you? ;) Thanks for the cat tip as it may just be required.

I believe the test involves three screenings. If you decell everytime you might be jinxing yourself! I have also heard if they cannot verify your vehicle by clearly recording your license plate you will not qualify.

DaveInDenver
03-11-2009, 10:52 AM
Correct! When you get your plate renewal notice it will state "No Emission Test Required" I have been exempt from test twice now and I hopefully will get the same news in a couple weeks when the post card should come.
Then it must be that my plates haven't been caught because the 4Runner (which is 100% stock) has had emissions test every time it's eligible. Probably Adolf Air Care just toying with me just to piss me off. If so, I can actually respect that.

Uncle Ben
03-11-2009, 10:55 AM
Then it must be that my plates haven't been caught because the 4Runner (which is 100% stock) has had emissions test every time it's eligible. Probably Adolf Air Care just toying with me just to piss me off. If so, I can actually respect that.

:lmao::lmao::lmao::lmao: "Adolf Air Care"......that could just keep me chuckling the rest of the day! Thanks! :thumb: :lmao:

PabloCruise
03-11-2009, 10:56 AM
Please keep us posted Crash, as I suspect EGR related malfunction is plaguing my 3FE...

Crash
03-11-2009, 10:58 AM
Please keep us posted Crash, as I suspect EGR related malfunction is plaguing my 3FE...

TJ, the EGR tests are very simple to perform. Do you have an FSM? If not I "think" I can scan the tests and email them to you.

DaveInDenver
03-11-2009, 11:10 AM
TJ, the EGR tests are very simple to perform. Do you have an FSM? If not I "think" I can scan the tests and email them to you.
Here's the one from the 22R-E and 3VZ-FE to give you some reference. It's not tough and probably similar on the 3FE.

Crash
03-11-2009, 11:39 AM
Here's the one from the 22R-E and 3VZ-FE to give you some reference. It's not tough and probably similar on the 3FE.

The 77exhaustq notes are very similar to the 3FE notes, just drop the 3,500 rpm test number to 2,500 for the 3FE.

leiniesred
03-11-2009, 01:08 PM
last month, for the FIRST TIME in my life, I have received a notice that I passed the roadside e-test and I didn't have to go to the station!

Sure it was in the MR-2 Spyder and not my truck, but it CAN work I guess.

I wasn't trying to pass the roadside e-test because my truck never passed even when I made a concerted effort to hit the roadside stations at the right time, right frequency, accelerating, blah blah blah.

It looks like you may need to be running REALLY clean to pass the roadside test. (The MR-2 Spyder is a ULEV rig)

Rzeppa
03-11-2009, 07:46 PM
X2 on what thefatkid wrote. EGR is all about NxOx. Stupid thing is, it is not an issue where we live due to our elevation. Higher combustion temps are what causes higher NxOx, and backing off on your timing may be the easiest way to pass, assuming your EGR is functioning as intended. I would look to these two areas before moving your registration.

PabloCruise
03-12-2009, 01:25 PM
The 77exhaustq notes are very similar to the 3FE notes, just drop the 3,500 rpm test number to 2,500 for the 3FE.

Man, you guys are awesome!

Much Gratitude!!!

leiniesred
03-14-2009, 09:45 AM
Talked to my father in law.
Crash: Go to aa performance muffler on broadway near hampden and talk to Scott.

The trick seems to be that cheap cats don't contain iridium. This shop has tested like 50 different cats before they found a good vendor. Bring your checkbook. It won't be cheap.

The other trick is to run race gas. The higher octane burns slower thereby lowering combustion temps and nox.

Crash
03-14-2009, 01:45 PM
Thanks Rudeboy! The cat that is on there now cam from AA but is about five years old or so but I will give them a call. I have a 50/50 mix of 91 and 100 octane in the tank now. Just brought home the secret weapon from Deano's after helping him stab his new Marlin tranny in his '85 Hilux this morning: the Weld Racing super lightweight wheels with some nearly, but still good enough, worn out BFG AT's that are each about 20 lbs lighter than the Eagle/Yokohamas that are on Bart now. That will help greatly in lessening the load on the engine while it is on the dyno. I'm buying the wheels back from Dean and will probably have some Eagle black rock crusher 15x8 wheels for sale real soon. Still waiting to hear from BVB for some inside poop and passing emissions and I'm sure he will have some good advice as have all the rest of you. Thanks!!

Uncle Ben
03-14-2009, 02:34 PM
Thanks Rudeboy! The cat that is on there now cam from AA but is about five years old or so but I will give them a call. I have a 50/50 mix of 91 and 100 octane in the tank now. Just brought home the secret weapon from Deano's after helping him stab his new Marlin tranny in his '85 Hilux this morning: the Weld Racing super lightweight wheels with some nearly, but still good enough, worn out BFG AT's that are each about 20 lbs lighter than the Eagle/Yokohamas that are on Bart now. That will help greatly in lessening the load on the engine while it is on the dyno. I'm buying the wheels back from Dean and will probably have some Eagle black rock crusher 15x8 wheels for sale real soon. Still waiting to hear from BVB for some inside poop and passing emissions and I'm sure he will have some good advice as have all the rest of you. Thanks!!


Easy, get rid of the anchor and install some domestic fuel injected powa! Problem solved! Vroooom!

Crash
03-14-2009, 10:56 PM
Easy, get rid of the anchor and install some domestic fuel injected powa! Problem solved! Vroooom!

Uh, you did that, didn't you UB? How soon after you made that "improvement" did you sell that truck? :lmao:

Uncle Ben
03-14-2009, 11:09 PM
Uh, you did that, didn't you UB? How soon after you made that "improvement" did you sell that truck? :lmao:

Good point! It was one of the worse choices I made....selling that truck! I wanted an 80 and the family hated the ugly brown pin striped interior of the 62 and wife put foot down and said one wagon was enough. Seriously, a fuel injected V-8 with 4L60E auto and two t-cases made that truck great! If and when I get another 62 I will do the exact same powertrain and put the whole thing on an 80 frame! ;) :thumb::thumb:

PabloCruise
03-15-2009, 08:17 PM
Thank you guys again for the help, here are some scans for 3FE EGR test from the '88 FSM if any future searchers come looking to lower their NOx...

My vac modulator caused the vac gauge to creep off 0 ever so slightly when engine cold @ 2500 RPM. I will replace, but I am wondering if this could cause loss of idle when hot...

I need to start a new thread on my 3FE.

leiniesred
03-16-2009, 08:55 AM
Crash: James' cat was about 3 years old and also from AA Performance.

Mendocino
04-04-2009, 01:15 PM
Can someone post a link to the statute/bureaucratic fiat that changed the Nox levels? I would like to better understand this.:mad: