Jaime-TA-84

iTrader: (1)

I went in for a pretest, even though I knew I would fail. Here are the results, and then I will give you more info about the car:
The technician told me the NO was high because of the catalytic converter or the EGR. I am currently running with an ECM from a 1987 Monte Carlo SS so I think the EGR solenoid is not even controlled by the ECM. I could be wrong, but I have not heard the solenoid clicking since I changed the ECM.

The hose that the technician failed me for was the hose that goes from that small cylinder thing that hangs in front of the carb and has a hose that goes to a thermostatic vacuum switch. The hose to the TVS was disconnected when he showed it to me so I need to get it replaced.

I'm going to put the old orignal ECM back and that will take care of the resisters I used to simulate a Baro sensor on the connector which he failed me for. I had to put the resisters on because the Monte Carlo SS ECM would show the check engine light since it needs a Baro sensor.

I changed from the original (I think) Oxygen sensor to a new Bosch sensor last year. I think it actually made my gas mileage go down by about 1 MPG (and since I only get 14mpg its a noticeable difference). How should I test them to see which one is actually better? I might end up putting the original one back.

I'm going to set the timing back to 6* BTDC. I'm also going to change the oil and oil filter, spark plugs, PCV valve. I changed the air filter a couple months ago.

Do you have any tips on how to lower the emissions? I need to get this done before May 8, but would rather do it sooner than later.

Kevin91Z

iTrader: (1)

Easiest way to lower the emissions is to install a new catalytic converter.

If the EGR solenoid is not working, that will cause the NO to be high.

You will need to hook up any and all wires and hoses. Anything the tech sees as disconnected, even if its not supposed to be there, is an automatic fail.

Bosch O2 sensors have a notorious failure rate on these boards. We all recommend the genuine AC Delco O2 sensors.

The timing has to be within three degrees of stock. I know the LG4/TBI cars is supposed to be zero degrees, and the TPI's are six degrees, but I dont know the L69 cars.

Lastly, have you been in the Southern California forum? Our next club meeting is Saturday April 5th in Torrance. We'd love to have you join us and we can discuss your car there.

NowTheBadNews

iTrader: (3)

I know early LG-4 & L-69 were set at 6 degrees base.

Jaime-TA-84

iTrader: (1)

I'm going to put the original ECM back into the car and probably a new AC Delco 02 sensor. There is a message at the bottom of the Pre-Test Inspection sheet that says "This vehicle failed the ignition timing check due to engine rpm being out of tolerance." I dont know what thats about. I'll set the timing back to stock, just in case thats what its referring to.

It would probably help if I took off the EGR valve and cleaned up all the passages, wouldnt it?

When told the smog tech what the resistors in the baro sensor connection were for and why I put them there, he told me I could just put it back behind the motor where it originally was and he wouldnt fail the car for that.

I'll see if I can make it to the meeting. It would be great if I could get some help with tuning the carb and other stuff. Maybe you guys could help me increase my gas mileage from the lousy 14 mpg I am getting.

EDIT: I just checked ACDelco.com for the stock oxygen sensor and it gave me two part numbers AFS20 and AFS22. Which one is the correct one for an L69? Either one? The AFS20 is $57 while the AFS22 is $39.

mouthforcombat

Moments like this make me a proud citizen of Minnesota, lol. Emissions? What are those? *drives down street with emissions & cat eliminated with header exhaust waking up all nearby neighbors*

Kevin91Z

iTrader: (1)

I bet your neighbors love you for making loud noises and polluting their neighborhood, too.

I think the AFS20 is the 3-wire sensor so you want the other one, which should be a single wire.

Yes it should help if you clean the EGR passages.

The RPMs being out of tolerance means you cant have the idle higher than 900 rpms. If that's not the case then I dont know.

Jaime-TA-84

iTrader: (1)

My idle is at around 600 rpm. The AC Delco site says the AFS20 is the OEM O2 sensor but the AFS22 is cheaper and listed as compatible so I'll give that one a try.

EDIT: I just got one from ebay that is listed as an AFS20 for $20. It says its an AFS20 but it has the number 22 stamped next to the circle with the letters AC inside of it. It has a single purple wire.

Kevin91Z

iTrader: (1)

I have some bad news for you. The latest SEMA newsletter just came in my inbox, and you better start writing your state representatives regarding HB863. It will bring California emissions standards and testing to your state if it passes.

Jaime, I'm glad you got the right O2 sensor. Its been so long since I've bought one I cant remember the numbers. Sorry for the confusion.

Jaime-TA-84

iTrader: (1)

I need some more advice/help Kevin.

Should I just take my car in and have it fail so I can use the Consumer Assistance Program to fix it? At first I though No, since I was thinking they would put me on a gross polluter list and have me go to a Test Only station forever. I would like your opinion on that.

Just in case I decide to fix the problem myself, I was looking at replacement catalytic converters for my stock L69. I found the following cats from Magnaflow at Summit:

MPE-93440 (Direct-Fit)
MPE-94019 (Universal)
Both say they are 3" inlet and outlet diameter, but I have read that no F-body came with 3" exhaust. So are these right?

Any other good cats for a stock engine?

87nosirocz

the nox is dew to the vacume not hook up thats what thermostatic switch goes to. it ported vacum from the carb and goes to the egr and air pump

Rayzor32

iTrader: (1)

Get a bottle of "guaranteed to pass" this stuff REALLY does work, it will lower your NOX by ALOT. Then have them run the whole test in 1ST GEAR, and see if you pass. trust me on this and try it The only thing you failed for was NO, the guaranteed to pass stuff should drop that to almost passing levels, and for some reason when you run it in 1st gear it produces less emissions. im almost positive this should work or at least get you very close. Another thing that will help will be to retard your timing just a little.

87nosirocz

NOX is is due to incomplete comustion the egr rec. the exaust gas through the egr valve reducing NOX. the catalatic coverter does the some thing if your cat is bad no adittives are going to help. check the cat with a temp gun if the cat is 100 deg hotter or more @ the rear. the cat is working if not you need to fix it or the air pump system. the air pump system inject air into the cat too get the cat to burn the NOX and CO and HC and turns it into water.

Jaime-TA-84

iTrader: (1)

I replaced the air pump a few months ago so that should be working properly.

five7kid

iTrader: (14)

Not true. NOx is due to high combustion temps, which can be excessive ignition advance, or improperly operating EGR valve. The purpose of the EGR valve is to dilute the air/fuel charge under certain conditions (such as high ignition advance conditions) to cool the combustion temperature.
I agree that if the cat is bad, no additives are going to help (the only time I used GTP, I still failed - the guts of the cat were completely gone).

The A.I.R. pump does not affect NOx. It provides extra oxygen to complete the combustion of any unburnt HC's (which produces H2O and CO2), and to convert CO to CO2.

Jaime-TA-84

iTrader: (1)

I put the stock ECM back on and the EGR solenoid is now clicking, although I dont know if the whole EGR setup works properly. How much difference does a disabled vs working EGR system make in terms of PPM of NOx? Maybe putting the stock ECM was enough to bring the NOx levels below the maximum?

Kevin91Z

iTrader: (1)

I wouldnt allow your car to become a gross polluter. It would open a whole new can of worms you dont want.

The EGR is a vital part of getting the NOx levels down to passable levels. If its not working you will have a harder time passing. You are allowed three degrees of initial timing in both directions. Stock TPI is 6 degrees before top dead center. However, three degrees will not affect the emissions much unless you're right on the edge of passing (like 10 numbers away).

NowTheBadNews

iTrader: (3)

Jaime ... Where do you live in so-cal? If close to riverside I can get you passed easy.

Jaime-TA-84

iTrader: (1)

I live in La Puente. It would be about a 1 hour drive. I'll probably do as much tuning up as I can (oil change, spark plugs, clean EGR valve and passages,set timing) and then do another pre-test to see if I'm going to need a new catalytic converter or not. Then I'll make the decision on whether to buy the new cat or take you up on your offer.

87nosirocz

im from La puente . i was born in west covina my dads side of the famly lives there, do you know jessie james? he's related, lillian james was my grandmother

Jaime-TA-84

iTrader: (1)

I dont know anyone around here since I'm just living here while I go to school. Do you still live in La Puente? I havent seen your car around.

Rayzor32

iTrader: (1)

I've seen thirdgens pass with no EGR, PVC, or AIR pump just a CAT. Tune up, guaranteed to pass and run it in first gear is how I got one to pass.

Jaime-TA-84

iTrader: (1)

I'm in California though. I doubt the smog tech will be willing to test in only 1st gear and I would definitely not pass without EGR, PVC, or AIR pump. I havent bought a new cat yet.

ezysk

Listening to you all talk about this really reminds me of when I lived in Canada and in PA, both had tests you had to pass in order to renew your plates. Canada was emission and safety while PA was only Safety. But I really did not like it. Even after you did all the right things so that your car would pass, some shops were scam artists that would fail you, just to get more money out of you. I know they were scamming when I would take the car to a different garage and it would pass with flying colors.

So I agree with mouthforcombat with the sentiment that I am so glad I don’t have to do the emissions and safety testing here where I live now.
Sure, I try to do things that will reduce pollution, but honestly if I was Mr. Super Environmentalist, I probably wouldn’t own a 3rd gen in the First Place.

I bet once you get your EGR working again, and possibly replace your converter if you think it needs it, and then you should pass.

87nosirocz

i live in colorado springs colorado that has no etesting witch is cool i can do what ever to my car. duel edelbrock 600 on tunnle ram runing e85 fuel 13.1 compresion, and the 4 gas says 25 hc and o CO at idle and 2500 rpm. it would pass exept the visual. have no egr or cat. no emesions crap at all. the car dynod @ 408hp @ 4500 and 468fttq @ 5000 this is at 6500ft above sea level. im a ASE master tech with 20+ in automotive. NOx is is due to incomplete combustion you are right about the EGR it suposed to decrease comustion temps to increase effeceny of the combustion chamber, the CATs job is to take stored CO2 and make a cemical rection to reduce HC CO and NOx. if i were working on your car first thing i would due is check ALL vacume lines and make sure everthing is working. next would be replace the plugs wires cap roter, set the timing chang the oil. and if its carb make sure the carb is set properly, it should pass as long as the is nothing wrong machanicly. bad compresion bad ring and so on.

midwest

No.
Nox is from too much heat, causeing nitrogen to bind with the 0xygen.
That is why a egr takes exhuast gas and dilutes the air. Basicaly adds inert gasses to reduce the combustion temps. high nox can be caused by too lean or too much timing.

Co is incomplete combustion. Which means that you have to much fuel.

Hc is unburned fuel. that means it didnt burn at all. Thats caused by a missfire, either igintion ( bad plug) , mechanical (bad valve) or Extreme
leaness or richness.

o2 is left over oxygen. Means theres not enough fuel. You compare co to o2. If o2 is higher then co you are lean, if co is higher then o2 you are rich.
Notice you dont look at hc to see if your rich. Hc is a missfire indicator.


Co2 is good, more the better. Co2 is what you get when you have a good afr. The higher the c02 the better your burning the fuel. Means both the mix, ignition and the the mechanical parts of the motor are all working good. 12- 14 percent is a good number for a motor with a cat. 8-10 for no cat.

Do not try to rationalize what i said, it will only get you confused.

Jaime-TA-84

iTrader: (1)

The stuff you mentioned kinda makes sense

I was digging through the paperwork I have collected for my car and found the smog check "results" of the smog check done the day before I bought the car:

All I have to say is WOW! No oxygen in the exhaust at all and extremely low amounts of CO and NOx. Keep in mind that these "results" were when the carb was in need of a rebuild, a bunch of hoses were disconnected or broken, sensors were failing, and the Check Engine light was on. Don't you all envy those "results"? lol Maybe I should go to the same smog check station that this smog check was performed at since its only a few minutes away

five7kid

iTrader: (14)

That doesn't say much for ASE, I'm afraid. You are completely wrong in your EGR theory. midwest stated it properly (although I would add the NOx is a combination of temp and pressure - raising either will raise NOx formation).

jaimegmr, why don't you have a baro sensor? Your car should have had it originally, a resistor isn't going to help getting it through emissions, and isn't going to hurt the way the car runs. Put it back like it should be.

My Berlinetta #2 passed both California and Colorado emissions. Believe it or not, it failed Colorado after passing California - after I put everything back in working order, as the factory intended (long story there), it sailed through the Colorado test.

Jaime-TA-84

iTrader: (1)

I looked around in the message boards after I put in the '87 Monte Carlo SS ECM and got the error code for the Baro sensor and came to the conclusion that since my car is a California emissions car (and was built here in Van Nuys) that it never had a Baro sensor. The stock ECM does not throw an error code for not having it and there is no bracket to mount the baro sensor to. The plug that goes to the baro sensor was cable-tied to the engine harness behind the motor.

This thread sort of confirms that CA cars did not have a Baro sensor (well, V6 ones, but its probably the same for V8)

five7kid

iTrader: (14)

That is from the V6 forum. They may be right about V6's, I don't have a clue.

gkrynick22

iTrader: (1)

This is why I love dealor plates. No emissions, no inspections, no registration, no insurance, no taxes... just slap a plate on her and go!

Oscar

I just went through some smog issues not to long ago. Kevin knows...but that is another story...The Consumer Assistance Program will not help you when you fail when things are modified. Modified means "not legal". In otherwords, they will not pay to unmodify the car. Go to a Gold Shield station, they should have the flier and application which explain it all to you. Then you'll have a better idea of how that works.

midwest

When you do an ecm swap you have to set the car up for the computer. Not rig the computer to think it has the baro. If the ecm needs a baro and it doesnt have one, it will not be able to work the way it was intended.

Jaime-TA-84

iTrader: (1)

I was faking the baro sensor for the '87 Monte Carlo SS ECM by supplying the ECM with a constant voltage that corresponded to what the baro sensor would output at my elevation.

Now that I have the original 84' L69 ECM, I do not need to fake the baro sensor since the ECM does not even seem to use it. (Federal '84 L69 ECMs probably use it, but I have reasons to believe that the California '84 L69 ECM does not.) Is anyone 100% sure its supposed to have a baro sensor?

I bought the '87 Monte Carlo SS ECM because I heard it was better and I was trying to rule out the ECM being the cause for my TCC not locking automatically, but I'm just going to stick with the original ECM and probably sell the Monte Carlo SS ECM. Now I think the ECM doesnt lock the TCC because there might be a problem with the 4th gear switch.

ljnowell

Wow. I gotta say, I am an ASE Master tech too, with about 5 years experience. I find it hard to believe that a 20 year certified master tech could not know this. Scary. But, then, there is always that one.

DENN_SHAH

iTrader: (1)

in one place my book says your car does not have a BARO, in another place it says it does. if the ECM isn't kicking a code it either doesn't use a BARO, or it does & its working right.
getting the right ECM & PROM back in the car with the timing right can do wonders for emissions.
get the other problems fixed & retest.

an example of some NOx readings i have gotten with no changes other than the EGR valve not working vs working, not working, anywhere from 1000~2500+ ppm,
working, from under 200 up to about 1200 ppm.
i've done this on a number of different vehicles on an actual emissions testing machine with the vehicles at running at 15 & 25 mph.
running in a lower gear helps because the motor isn't loaded as much at the higher rpm.

im a ASE master with L1, 30 years in the field, man im old.
any of you other wrenches on iatn?

87nosirocz

why is it then i have a car that has no emisions on it and still produce low enoph leves to pass california emisons standerds? i will tell you why its called comubustion efficancy. there is no nox on a fives gas analizer no CO and very little HC. and i know how to tune a car. dont be an *** to me you have no clue who i am.

87nosirocz

Read and educate your self im right and you wrong and your ase. High amont of NOx is a lean mix and low NOx is a rich mix so it does have something to incomplete combuston. and its dew to a lean missfire.

Jaime-TA-84

iTrader: (1)

What book is that from? Looks like a lot of possibly good info, although the part that you highlighted basically contradicts itself. Major typo error at the bold parts.

"When the mixture is slightly rich, there is less chance that NOx will be produced but greater chance that CO and HC emissions occur. Likewise when the mixture is slightly rich, there is less chance that CO and HC emissions will ocurr but greater chance that NOx will be produced."

87nosirocz

the book that i got when i when to school for this. i have a degree in automotive and a enganeering degree in automotive.

BretD 88GTA

You can't run the test strictly in first gear, BUT see if the tech. will manually shift the trans. This is what I do on my car and it helps it blow better NO numbers because you can run the RPM's up higher in each gear.

ljnowell

i really dont care if your car passes emissions standards or not. You really in essence just proved yourself wrong. With a lean mixture, especially to the point of misfire, the combustion temperature goes up. That increase increases the oxides of nitrogen (NOx) in the exhaust. Any ASE certified technician should know this. You should also know that the industry accepted magic number is 2500 degrees. The goal of egr is to keep the temps down to that point.

DENN_SHAH

iTrader: (1)

87nosirocz, you can take a car that is running on the rich side & with nothing more than advancing the timing drive NOx way up. you can also take a motor that is lean & reduce NOx by pulling timing out. try it some time on the 5 gas.
as ljnowell said, its because of the heat, at 2500 degrees NOx production spikes.

Kevin91Z

iTrader: (1)

A degree in engineering and you spell worse than a fifth grader? Oh well, it doesnt matter because we can still understand you, right?

Your knowledge will be more readily accepted if you present it in a clear and informative matter. Being hostile and acting like a bully will get you nowhere around here, nor in real life.

87nosirocz

try running 10% E85 that will bring the NOx levels down too. i spell bad because i didnt grow up playing on the computer its not my spelling its the typing the gets me. im 45 years old the didnt have computers when i was growing up typing was done on a typrighter not a computer and how often does enyone use a typerighter. Your talking about me being the bully i just made a statment and all you all did is insult my inteligence what kind of crap is that.

87nosirocz

I know this, why are you telling me this, this is not what was being descused. NOx is due to hi combustion temps i know this what im tying to get at is the effecancy of the combustion chamber depends on the fuel mixture, too rich you have a rich misfire witch will increses HC levels and a leen mix will increses NOx do to high comustion temps and HC levels if there is a leen misfire. aparenty none of you have ever had to tune a car at a emesions station you would know this. this a form not a spelling test who cares about spelling.
I DONT!!!!!!!!!!!

DENN_SHAH

iTrader: (1)

the way you said it, you made it sound like combustion chamber temps had little to nothing to do with NOx, that it was only the mixture & efficiency of the motor.

you say you have 20 years in the field of auto repair, i've been doing driveability longer than that.
i have had my L1 cert for 14 years.
the shop im at has been a state certified official emissions repair facility sense around February of 95. we are also Air Check Texas certified.
i have repaired a few emissions failures

as far as the spelling goes, im not that great at it either. you can download the Netscape 4.8 browser. it comes with a program called Composer which has a pretty good spell checker. for a free program, its great

Jaime-TA-84

iTrader: (1)

I finally cleaned my timing tab today and found that the timing on my car was actually set at 8 degrees instead of 6 degrees. I set it to aproximately 5-6 degrees today. Hopefully that lowers my NOX below the max passing level. Need to take it in for a smog check ASAP so I'll let you know the results.

Guest

Something is missing from that book excerpt, like why the O binds with the N and forms the various NO compounds. If you research different fuels and different conversion methods, you might find the error in your statement. High combustion temperatures allow N and O to bind and form the various NO in a running internal combustion engine. Ask yourself why a lean misfire would cause NO? A lean misfire causes a high temperature condition within the cylinder, and allows NO to form. So you need to read and educate yourself a little more.

Kevin91Z

iTrader: (1)

You're allowed 3 degrees, so if your timing is set from 3 degrees to 9 degrees you're fine. Having it off by 2 degrees is not going to make your NO fail. You probably have a bad injector, or a bad O2 sensor, or the catalytic converter has just completely failed.

Rayzor32

iTrader: (1)

retarding the timing a little will reduce NOx. When I had to help an out of state friend with his emmisions, that guaranteed to pass stuff lowered his NOx by over 400 points, and new spark plugs, wires, rotor, cap, and oil did next to nothing and it needed a tune up. They usually will let you run some test runs, the guy we had we told to run the whole test in 1st gear (15 and 25mph tests) and doing that just got it to pass, by 1 point but it passed but what a PITA im glad i dont live in an emmissions state id never pass