Just barely made it.
Thread Starter
Pro
Joined: Dec 2002
Posts: 522
Likes: 3
From: Rolling Meadows IL
Just barely made it.
I just barely passed the emissions test IM240 composite fast pass ( no idea what that means). HC was 0.393 and the limit was 0.407. CO was 0.690 and the limit was 3.804. The test is on a dyno. I have a CAT and AIR pump. It fails without them. Does anyone have any results they can share. The car is an 85 without a cold start valve so I know it’s not leaking and the Ford injectors are only a couple of years old. I am wondering why HC is so close.
Race Director
Joined: Nov 2004
Posts: 14,145
Likes: 142
From: Central Il
Not to hi-jack your thread, but we don't have emission testing here in downstate Illinois. I was curious is it just Cook County that has testing or does it encompass a larger area?
Thanks.
Thanks.
Burning Brakes
Joined: Feb 2004
Posts: 1,085
Likes: 7
From: Kanata ON.
I JUST passed the emissions on my 88 vert last week, the HC were just under the limit ( I don't have the numbers in front of me right now ). The mechanic said that it was probably due to the new plugs and wires I had installed and the computer was still learning. I certainly hope he's right, I will know in two years from now! 
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
the air pump does nothing once the engine is hot. So it will have little effect on the numbers.
As for high HCs? I would suspect the cats are not up to snuff.
Do they do a visual? If not, I would ditch the pre-cats and get a highflow main cat.
which FMS injectors did you use? If you used the 24# units on that engine, without an AFPR, it would cause a rich condition. So would a sluggish O2 sensor. If your plugs are a bit old, that would contribute.
As for high HCs? I would suspect the cats are not up to snuff.
Do they do a visual? If not, I would ditch the pre-cats and get a highflow main cat.
which FMS injectors did you use? If you used the 24# units on that engine, without an AFPR, it would cause a rich condition. So would a sluggish O2 sensor. If your plugs are a bit old, that would contribute.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
Your'e right, that was close!! Curious to hear more on this. Seems these vettes are always close or are failing, mine included. Its been told to me repeatedly to decarbon the TB and intake (using seafoam) to help.
Any smog techs in the house?
Any smog techs in the house?
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Racer
Joined: Oct 2001
Posts: 421
Likes: 0
From: Simi Valley CA
Just a few weeks ago I smogged my vette and one of the limits was really really close.
Without looking at the sheet I can't tell you which thing it was but the range max is something like 1324 and mine was 1322, It was the same last time I smogged it too.
Without looking at the sheet I can't tell you which thing it was but the range max is something like 1324 and mine was 1322, It was the same last time I smogged it too.
Drifting
Joined: May 2002
Posts: 1,581
Likes: 2
From: The Motor City
I've got to go do my '89 soon as well. I was really close the last time too - HC limit is 200ppm and my car registered 149ppm. That was at idle; HC limit at 2500rpm is the same as idle (200ppm) but my car registered only 22ppm.
The mechanic said it was nothing that a good tune-up wouldn't take care of. But the car had new Mobile 1 15W-50 oil and oil filter (after performing an engine flush), the AC Delco plugs where only a couple of years old and I checked their gap only a few days earlier, it had a brand new K&N air filter (with cut lid), and I had just adjusted the timing to factory spec. Other than replacing the plug wires, what else could I have done to 'tune' it up?
But a pass is a pass. Hopefully, when I take it in this time, it will pass again. Once the car becomes 20 years old, it won't have to go through any more emissions tests.
The mechanic said it was nothing that a good tune-up wouldn't take care of. But the car had new Mobile 1 15W-50 oil and oil filter (after performing an engine flush), the AC Delco plugs where only a couple of years old and I checked their gap only a few days earlier, it had a brand new K&N air filter (with cut lid), and I had just adjusted the timing to factory spec. Other than replacing the plug wires, what else could I have done to 'tune' it up?
But a pass is a pass. Hopefully, when I take it in this time, it will pass again. Once the car becomes 20 years old, it won't have to go through any more emissions tests.
Pro
Joined: Feb 2005
Posts: 658
Likes: 1
From: Centerville OH
I just had my 89 emissions checked -- FOR THE LAST TIME (Ohio is eliminating emissions testing in my county). 
I eliminated the pre-cats 10 years ago but all other emissions devices are hooked up. I passed on the second try -- the EGR valve was stuck open on the first try and I failed for NOx. Fortunately, I was able to fix the issue with a ball peen hammer and a socket extension. However, I did use this as a justification to replace the 12 yr. old. Mallory plug wires with MSD wires and change the plugs, cap, rotor, and PCV valve. The oil was changed about a month ago. Base timing is 12 deg.
My numbers are as follows:
HC -- 79.5 ppm (152 ppm limit)
CO -- 0.08% (0.97% limit)
CO2 -- 12.73%
NOx -- 801 ppm (1082 ppm limit)
I eliminated the pre-cats 10 years ago but all other emissions devices are hooked up. I passed on the second try -- the EGR valve was stuck open on the first try and I failed for NOx. Fortunately, I was able to fix the issue with a ball peen hammer and a socket extension. However, I did use this as a justification to replace the 12 yr. old. Mallory plug wires with MSD wires and change the plugs, cap, rotor, and PCV valve. The oil was changed about a month ago. Base timing is 12 deg.
My numbers are as follows:
HC -- 79.5 ppm (152 ppm limit)
CO -- 0.08% (0.97% limit)
CO2 -- 12.73%
NOx -- 801 ppm (1082 ppm limit)
Last edited by Z51L9889; Jul 29, 2005 at 09:40 PM.
Thread Starter
Pro
Joined: Dec 2002
Posts: 522
Likes: 3
From: Rolling Meadows IL
Originally Posted by bogus
the air pump does nothing once the engine is hot. So it will have little effect on the numbers.
As for high HCs? I would suspect the cats are not up to snuff.
Do they do a visual? If not, I would ditch the pre-cats and get a highflow main cat.
which FMS injectors did you use? If you used the 24# units on that engine, without an AFPR, it would cause a rich condition. So would a sluggish O2 sensor. If your plugs are a bit old, that would contribute.
As for high HCs? I would suspect the cats are not up to snuff.
Do they do a visual? If not, I would ditch the pre-cats and get a highflow main cat.
which FMS injectors did you use? If you used the 24# units on that engine, without an AFPR, it would cause a rich condition. So would a sluggish O2 sensor. If your plugs are a bit old, that would contribute.
I used the FMS 21# injectors and adjusted the injector constant to give good BLM’s. I have a 165 ECM. I have a new wideband O2 with a simulated narrow band output driving the ECM. It’s not rich.
I did find the document that defines the IM240 fast test. Basically after 30 seconds there are tables they use to determine the limits for every second from 30 to 240 for different years. If your car is under these limits it passes and the test is stopped. My car passed after 31 seconds. Now I know that is as fast as it could pass.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Ralph.
Check out the innovate wb sold in summit. THey are around 350 got one that I am using with my DFI and it too can simulate a narrowband, it can log and it has addons that you can log RPM with it. Very nice unit with the cheaper wb02 sensor. My tech edge I had, that Dad is using in the chevelle now, cost over 350 dollar by itself!
If you need some information just let me know. It can hold the logs and you can download them onto your PC when you get home and plot them out with their software. I never did that since the DFI does all that for me.
Check out the innovate wb sold in summit. THey are around 350 got one that I am using with my DFI and it too can simulate a narrowband, it can log and it has addons that you can log RPM with it. Very nice unit with the cheaper wb02 sensor. My tech edge I had, that Dad is using in the chevelle now, cost over 350 dollar by itself!
If you need some information just let me know. It can hold the logs and you can download them onto your PC when you get home and plot them out with their software. I never did that since the DFI does all that for me.
Thread Starter
Pro
Joined: Dec 2002
Posts: 522
Likes: 3
From: Rolling Meadows IL
Le Mans Master
Joined: Feb 1999
Posts: 6,170
Likes: 11
From: somers, ny
Originally Posted by dave_85
Thx Dave.
Jesse you have mail. (2 of them)
Thread Starter
Pro
Joined: Dec 2002
Posts: 522
Likes: 3
From: Rolling Meadows IL
A few nice things about the Zeitronix Zt-2 is it is very small, uses the cheaper Bosch sensor, comes with an input for RPM, TPS. You can plot A/F, RPM, TPS and use this graph to tune your chip. I found it very easy. I have mine hooked up all the time. One down side is you need a PC running in your car to see/collect log data.