aircooler

Hi Garth, your PM box is full big guy!

Thanks for the tip Earl.

Mike

jadavis01

I think your cruise rpm is low and causing you to fail.I recently failed an emmissions test on the cruise portion but passed the idle test with no cats. When looking over the report I noticed the cruise rpm was around 1200 which I thought was to low so I decided to try it again in low gear at about 2600 rpm and it passed the second time around.

rsneek928

Mike,

Look forward to meeting you some time.

Just checked out your website. Holy sh*t man are you a glutton for punishment or what? Nice work on the car, good to see it didn't get scraped.

ROG100

Mike,
You may have seen my thread on the same subject.
I have fitted a different cat, new O2, checked the air pump to the cat, checked the computers to make sure I have no added chips.

Currently fitting a new MAF and checking the vacuum system. Also adding Techron to my gas.

A year ago sailed through with no problems. Same test criteria this year and failed with high NOx. Tested 6 times at various points and all failed with the same high NOx. No change with any of the mods.

I have read a lot of posts about fuel quality and gummed up injectors. I am as a matter of course going to keep to one type of gas - Chevron and use Techron every month. I did use a lot of cut price gas - premium though - from Tom Thumb - this may be the reason why my mixture is lean????

I tried asking to run the test in second gear (ATM) to increase the revs, however they will not play ball. I will take the car to another test station and try asking again.

If I fail the test with the new MAF and have confirmed I have no vac leaks I am going to apply for a waiver. Here in Texas if you can show you do less than 5K miles per year and that you have spent a few bucks on trying to solve the problem they will issue a waiver.

Best of luck
Roger

ViribusUnits

Sometime injectors just develop problems. MAybe they came from the factory with a imperfection in the rubber. Maybe you got just a little too much methanol in one perticular tank of fuel. Maybe one tank of fuel developed some strange normaly insouable to gasoline junk.

It happens.

It comes with owned a 10 year or, or 20 year old car. You just pull the injectors figure out which one is bad, and then get it repaired or replaced.

Randy V

Have the tech run the car in reverse - this will result in negative values for all constituent pollutants.

Yes, it's true - running in reverse actually CLEANS the air!

mspiegle

LOL.... thats a good one =)

Koenig-Specials 928

Mike, My 89 GT just passed (even barely) its emission test in Toronto today.
I have gutted Cats also. The O2 must work. It had failed the test last week but the wrench told me to fill the tank with Sunoco 94 Octane, add a can of additive that "guarantees you to pass" or money back from Canadian Tire, run the car until the tank is empty (min 250 Km), refill with 94 Octane, take the car for a hood hot run and test it. I did all of that and for spending less than $50 it passed. If you still have problems, please write to me.
Hessank
89 Koenig

AO

Hessank reminds me of another point; make sure your car is good and hot. Not a 5 min run, but a good 20 minute run at high rpms. You want that sucker as hot as you can get it. Make sure you're running AC full-tilt-boogie to aid in heat soak. If you have to wait in line, make sure you don't turn off the engine. Let it idle away and keep the AC on. This should aid in lowering a few of the numbers... but sadly, probably not enough to get you to pass by itself, but every littel bit helps.

Good luck.

ViribusUnits

No you don't eighter.

You do not want an overheated engine. High combustion chamber temps will cause you to fail the emissions test with high NOx.

Higher engine temps result in higher peak combustion chamber temps.

So, do not get it as hot as you can. Get it near the middle of the temp guage, and call it good.

SharkSkin

Well, it worked in this case and it's worth trying for a number of reasons. First, it ensures that the cats are real hot. The hotter the better, because they need heat to operate. It also ensures that the fuel atomizes completely, because you want it to burn completely to reduce HC. Higher octane can help with this too. In fact, the higher octane will tend to reduce NOx because it reduces detonation so that can be a balancing factor. Also higher octane will tend to burn more completely.

Bottom line, getting it real hot is something worth trying. If you can't just drive it to the smog shop and have it pass without sweating anything(like my shark did) then this is a very, very simple thing thing to try. Hot is good, not to the point of overheating, but certainly to the point where it is completely heat soaked and the cats are as hot as possible.

ROG100

Mike,
I passed the test.
See my thread "failed emission test"
Best,
Roger

aircooler

Hello guys.

Thanks again for all the input.

As my emissions test data is showing exceptionally high HC ppm, CO% and NO ppm, I think that I may have a similar MAF issue to that of ROG100.

Roger, GREAT NEWS! I will be trying to get in touch with John S. to get his opinion. That might have been me sitting behind you in that boat you just stepped out of. I was the one talking to himself and going out of his way to irritate the others

VB, right now I am not putting any chips on the injectors, that may change though . I had them all serviced last November and they were 100%. Re: heat, I would defiantly recommend hot cats for an emission test. The hotter they are, the more efficient they are at burning up/cleaning the emissions. Many a good dollar is wasted at "Certified AirCare repair facilities" by those that parked their cars there all day before the test.

Garth, when I get my "strait pipes" off the car I will look for an isolated O2 just as you suggested. That may very well be a piece of the puzzle.

Randy, if you drive your 79 backwards, will you get your roof back?

Hello Hessank, good to read from another local shark! What is that CT stuff? Sounds kind of hoakey?

Cheers all,
Mike

ViribusUnits

I agree, everything up to opperating temp is good. Bring the cats, engine coolant, and engine oil up the opperating temp.

However, hotter is not always better. You can overshoot the mark, and end up failing because the engines too hot. Basicly, my point being don't overheat the engine thinking it'll get you through the testing.

DG84S

Mike,
My '84S failed twice for high NOx...the wrench said it needed new cats. HC and CO were well under limits. I replaced the air pump (almost no output), replaced the oxygen sensor (it was the original with 100K miles) and adjusted the timing (it was too advanced). Passed easily!
High NOx is generated by elevated combustion chamber temps...from running too lean or with timing too advanced.