How did they do that?
Thread Starter
Melting Slicks
Joined: Mar 2010
Posts: 2,967
Likes: 43
From: Bradenton Florida
2017 C4 of the Year Finalist
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
How did they do that?
Hi, I am new to the forum, I just purshased an 06 coupe, with 9600 miles from a dealer in Illinois. Our state mandates emission controls, and does inspections. Upon inspection under the car I found out that the original owner had eliminated the cats, and rear O2 sensors. Highly illegal in our state, and never should have been sold in its current condition. My question is how did they bypass the rear o2 sensors? There are no simulators that I can see, just the empty plugs from the sensors. The check engine light is working, lights up and then goes off on starting. I tried to check for error codes with my code reader, but only get error message on the reader. I have been told that you can tune out the rear o2 sensors???? I want to buy the cats for a Kooks header system, and put the o2 sensors ( rear ) back in. I want the ecm to function as normal again ( stock tune ) then I will tweak as necessary. Will a reflash of the ecm do it? As this was done at a shop somewhere, I don't have the original tune to upload back into the car. Any help would be greatly appreciated. Thanks
Melting Slicks
Joined: Mar 2007
Posts: 2,391
Likes: 23
From: Santa Barbara CA
Sounds like someone removed the sensors and just "turned off" the related codes and functions for them with tuning software. Does the car have Kooks headers? If so, then you could just buy the needed cats and possibly X-pipe from them. The truth is that no long tube headers are smog legal, even ones with high-flow cats. It still won't technically be smog legal, but it should pass the sniffer. If you want the car to be 100% emissions legal, then you need to install OEM cats and manifolds.
I would recommend finding a quality tuner in your area and have everything tuned properly after you get the cats/02s installed.
Andy
I would recommend finding a quality tuner in your area and have everything tuned properly after you get the cats/02s installed.
Andy
Thread Starter
Melting Slicks
Joined: Mar 2010
Posts: 2,967
Likes: 43
From: Bradenton Florida
2017 C4 of the Year Finalist
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
Thanks, I talked to the air team people today (that's what they call the watchdogs ) and they said they didn't check visually for what type of cats were there. The dealer just told me to take a hike....so I'm on my own now. I will let our states attorney hash that out. The Air team said that as long as the computer says OK, it should pass. I'm going tomorrow to see what the car actually does with the emmission cops. I told the dealer that he just sold an illegal car and he doesn't care. The EPA might be interested. In our state they either suspend your license or won't renew your plates. I just want something back under there to be at least kind of compliant. Will a re-tune turn on the back o2 sensors? Will the hand held devices available work, or are we talking pc type tuning? Yes Kooks long tubeheaders, x pipe but no cats.
Safety Car
Joined: Jan 2008
Posts: 4,711
Likes: 3
From: Middle of No where AK
I dont recall how to reactivate the o2's but a reflash may alter the way the car drives as well. The tune was probably altered to run better with the headers so you may want to find a mail order tuner like ECS or chuck cow or even LG to reactivate that part of your system.
It also sounds like your dealer is a real tool. I would turn his azz in with a quickness since he is so quick to toss you aside after a purchase. Let the dealer get raked over the coals for screwing you over. They friggin know better.
Thread Starter
Melting Slicks
Joined: Mar 2010
Posts: 2,967
Likes: 43
From: Bradenton Florida
2017 C4 of the Year Finalist
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
According to the guys at the testing place, they don't know or even care what's under the car. I don't think they even have the sniffer anymore, we will see tomorrow! If it fails, just more ammo for the Judge! It is illegal to sell car in Illinois without emissions! Yes they know, he's banking on me going away. They really wanted this car back! They are screwed now! I went tonight and grabbed my car back! The other reason for adding the cats is to try and quite down the exhaust a bit, it really drones in 4-5th gears right where you spend time in traffic. I was thinking of adding some hushmat to the back trunk area.
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
I suggest you read up on the test requirements.
The state test will plug in the OBDII port and look for "readiness" state and MIL codes. They also do a tailpipe sniff test at idle. To pass the "readiness" test, you need to either get the rear cat's working or shut off the reporting of the "readiness" test for the cats using tuner software such as HP Tuners. This last one is illegal under the EPA.
Here is part of what the state put on their website.
http://www.epa.state.il.us/air/vim/about.html
The state test will plug in the OBDII port and look for "readiness" state and MIL codes. They also do a tailpipe sniff test at idle. To pass the "readiness" test, you need to either get the rear cat's working or shut off the reporting of the "readiness" test for the cats using tuner software such as HP Tuners. This last one is illegal under the EPA.
Here is part of what the state put on their website.
http://www.epa.state.il.us/air/vim/about.html
About the Test: Understanding the Illinois Vehicle Emissions Test
What Vehicle Emissions Tests are Performed in Illinois?
Two different types of tests are used in Illinois.
* An OBD test (On Board Diagnostics) is used for most 1996 and newer model year passenger cars and light duty trucks, including vans and sport utility vehicles.
* A single-speed idle exhaust test and gas cap pressure test is used for gasoline-powered heavy duty trucks and certain passenger cars and light duty vehicles that were certified by the federal government to be manufactured without OBD systems.
How is the OBD test performed?
The OBD test consists of connecting a scan tool to a vehicle's on-board computer to determine the OBD system status (readiness checks), to determine whether the Malfunction Indicator Light (MIL) is commanded to be illuminated, and to retrieve any stored diagnostic trouble codes.
Vehicles will pass the OBD test if the OBD system is working, all required emissions system readiness checks have been completed, and the MIL is not commanded to be illuminated.
Vehicles will fail the OBD test if the MIL is commanded to be illuminated and diagnostic codes are present. Vehicles will also fail if the OBD system is inoperable or if the OBD connector is missing, damaged, or inaccessible.
Check the “Understanding On-Board Diagnostics (OBD)” frequently asked questions page for further information.
How are the Idle Exhaust and Gas Cap Tests Performed?
Idle Exhaust Test
The idle exhaust test uses a tailpipe probe and emissions analyzer to measure the level of ozone-forming exhaust pollutants (carbon monoxide (CO) and hydrocarbon (HC)) in the vehicle's exhaust at idle speed.
If the levels of both of these pollutants are below applicable standards, the vehicle will pass the idle exhaust test. If the levels of one or both pollutants is above the applicable standard, the vehicle will receive a second-chance test following a period of high-idle preconditioning. If the level of either pollutant is still above the applicable idle test standards when re-tested, the vehicle will fail the idle test.
Gas Cap Test
The gas cap test is a functional check of the gas cap's seal. This test determines whether excessive levels of evaporative emissions (gasoline fumes) can escape from a vehicle's gas tank into the atmosphere. The gas cap is removed from the vehicle's fuel tank filler neck and attached to the testing unit which then applies pressure to the gas cap to check for leaks. If the gas cap cannot maintain the prescribed pressure, the vehicle will fail the gas cap test.
Check the “Understanding Idle Tests and Gas Cap Tests” frequently asked questions page for further information.
What Vehicle Emissions Tests are Performed in Illinois?
Two different types of tests are used in Illinois.
* An OBD test (On Board Diagnostics) is used for most 1996 and newer model year passenger cars and light duty trucks, including vans and sport utility vehicles.
* A single-speed idle exhaust test and gas cap pressure test is used for gasoline-powered heavy duty trucks and certain passenger cars and light duty vehicles that were certified by the federal government to be manufactured without OBD systems.
How is the OBD test performed?
The OBD test consists of connecting a scan tool to a vehicle's on-board computer to determine the OBD system status (readiness checks), to determine whether the Malfunction Indicator Light (MIL) is commanded to be illuminated, and to retrieve any stored diagnostic trouble codes.
Vehicles will pass the OBD test if the OBD system is working, all required emissions system readiness checks have been completed, and the MIL is not commanded to be illuminated.
Vehicles will fail the OBD test if the MIL is commanded to be illuminated and diagnostic codes are present. Vehicles will also fail if the OBD system is inoperable or if the OBD connector is missing, damaged, or inaccessible.
Check the “Understanding On-Board Diagnostics (OBD)” frequently asked questions page for further information.
How are the Idle Exhaust and Gas Cap Tests Performed?
Idle Exhaust Test
The idle exhaust test uses a tailpipe probe and emissions analyzer to measure the level of ozone-forming exhaust pollutants (carbon monoxide (CO) and hydrocarbon (HC)) in the vehicle's exhaust at idle speed.
If the levels of both of these pollutants are below applicable standards, the vehicle will pass the idle exhaust test. If the levels of one or both pollutants is above the applicable standard, the vehicle will receive a second-chance test following a period of high-idle preconditioning. If the level of either pollutant is still above the applicable idle test standards when re-tested, the vehicle will fail the idle test.
Gas Cap Test
The gas cap test is a functional check of the gas cap's seal. This test determines whether excessive levels of evaporative emissions (gasoline fumes) can escape from a vehicle's gas tank into the atmosphere. The gas cap is removed from the vehicle's fuel tank filler neck and attached to the testing unit which then applies pressure to the gas cap to check for leaks. If the gas cap cannot maintain the prescribed pressure, the vehicle will fail the gas cap test.
Check the “Understanding Idle Tests and Gas Cap Tests” frequently asked questions page for further information.
Thread Starter
Melting Slicks
Joined: Mar 2010
Posts: 2,967
Likes: 43
From: Bradenton Florida
2017 C4 of the Year Finalist
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
Anyone know where to get a tune in Northern Chicago suburbs? I will need after the cats.
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Thread Starter
Melting Slicks
Joined: Mar 2010
Posts: 2,967
Likes: 43
From: Bradenton Florida
2017 C4 of the Year Finalist
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
If it won't pass, then I will get my attorney after them, they told me yesterday that they were going to put the factory exhaust back on, after they saw the cost, they told me to go take a hike..... soo I guess we will see if it will fly. They talked to the original owner and called the shop where the work was done, they claim it will pass, but when I called the other day, they were very clear for off road use only.
Le Mans Master
Joined: Nov 2002
Posts: 7,179
Likes: 2
From: Charlotte, NC
If it won't pass, then I will get my attorney after them, they told me yesterday that they were going to put the factory exhaust back on, after they saw the cost, they told me to go take a hike..... soo I guess we will see if it will fly. They talked to the original owner and called the shop where the work was done, they claim it will pass, but when I called the other day, they were very clear for off road use only.
If you want/need to go back to stock look around the forum, craigslist, e-bay maybe you can find a used setup from someone who installed long tubes... for a much lower price then new...
-=Rick
Drifting
Joined: May 2006
Posts: 1,709
Likes: 18
From: Montgomery Il.
If it won't pass, then I will get my attorney after them, they told me yesterday that they were going to put the factory exhaust back on, after they saw the cost, they told me to go take a hike..... soo I guess we will see if it will fly. They talked to the original owner and called the shop where the work was done, they claim it will pass, but when I called the other day, they were very clear for off road use only.
Pro
Joined: Mar 2008
Posts: 620
Likes: 3
From: Harwood Heights IL
You should pass emissions no problem, as long as there is no check engine light on
and as to the drone, you can get a cats and resonators welded into the x-pipe and it will quiet the car down a lot
these guys tuned my car last fall http://1320hp.com/ they are a forum sponsor, give mike a call there and he will probably explain to you how this works
I also have stock parts sitting under my porch (intake/headers/cam etc), but I am not sure I am ready to part with them....
does your intake manifold say FAST on it by any chance?
and as to the drone, you can get a cats and resonators welded into the x-pipe and it will quiet the car down a lot
these guys tuned my car last fall http://1320hp.com/ they are a forum sponsor, give mike a call there and he will probably explain to you how this works
I also have stock parts sitting under my porch (intake/headers/cam etc), but I am not sure I am ready to part with them....
does your intake manifold say FAST on it by any chance?
Speedy
Joined: Mar 2007
Posts: 6,109
Likes: 931
From: Tn
2024 C8 of the Year Finalist - Modified
to answer your question:
when a tuner tunes a vehicle they have the ability to tell the computer to ignore the rear o2 sensors, you WILL pass emissions with NO PROBLEMS because all the emissions test does is ask the computer if it has seen any abnormalities with the emission system; because your computer is ignoring the rear o2 it has no way to tell that the cats are gone.
if you are legitimently worried about the well being of the environment and being emissions compliant you should install the oem exhaust as NO AFTERMARKET exhaust is smog legal
i have my entire stock exhaust taken off around 5k miles with new gaskets, i live in illinois and will beat the dealers price for exhaust system
when a tuner tunes a vehicle they have the ability to tell the computer to ignore the rear o2 sensors, you WILL pass emissions with NO PROBLEMS because all the emissions test does is ask the computer if it has seen any abnormalities with the emission system; because your computer is ignoring the rear o2 it has no way to tell that the cats are gone.
if you are legitimently worried about the well being of the environment and being emissions compliant you should install the oem exhaust as NO AFTERMARKET exhaust is smog legal
i have my entire stock exhaust taken off around 5k miles with new gaskets, i live in illinois and will beat the dealers price for exhaust system
Thread Starter
Melting Slicks
Joined: Mar 2010
Posts: 2,967
Likes: 43
From: Bradenton Florida
2017 C4 of the Year Finalist
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
I took it this afternoon, they charged me $20.00 to run the test. I had the guy I talked to yesterday, he KNEW there were no cats, he didn't care, he just plugged in the computer and waited for his time to clock out. Friggin car passed! No cats, exhaust stunk it was so rich in the testing lane after idling ten minutes. They just don't care! They knew there were no cats, they just don't care! I'm totally shocked. I have had cars with all emissions flunk due to a gas cap! Total disbelief!
Safety Car
Joined: Jan 2008
Posts: 4,711
Likes: 3
From: Middle of No where AK
I took it this afternoon, they charged me $20.00 to run the test. I had the guy I talked to yesterday, he KNEW there were no cats, he didn't care, he just plugged in the computer and waited for his time to clock out. Friggin car passed! No cats, exhaust stunk it was so rich in the testing lane after idling ten minutes. They just don't care! They knew there were no cats, they just don't care! I'm totally shocked. I have had cars with all emissions flunk due to a gas cap! Total disbelief!
Speedy
Joined: Mar 2007
Posts: 6,109
Likes: 931
From: Tn
2024 C8 of the Year Finalist - Modified
I took it this afternoon, they charged me $20.00 to run the test. I had the guy I talked to yesterday, he KNEW there were no cats, he didn't care, he just plugged in the computer and waited for his time to clock out. Friggin car passed! No cats, exhaust stunk it was so rich in the testing lane after idling ten minutes. They just don't care! They knew there were no cats, they just don't care! I'm totally shocked. I have had cars with all emissions flunk due to a gas cap! Total disbelief!
Team Owner
Joined: Oct 2004
Posts: 27,420
Likes: 64
From: San Clemente CA
If the EPA found out about your dealer selling the Corvette with the cat's removed, 02 sensors tuned out and a tune they would be in big trouble. It's a Federal crime, not just your state. In California the fine is $30,000. 
Tech Contributor
Joined: Oct 1999
Posts: 41,037
Likes: 9,801
From: Charlotte, NC (formerly Endicott, NY)
From the parts of the Illinois regulation that were printed above it clearly says that for 1996 and newer cars all they have to do is pass the OBD II test. It doesn't matter about anything else. Computer says it is good it is good.
Two different types of tests are used in Illinois.
* An OBD test (On Board Diagnostics) is used for most 1996 and newer model year passenger cars and light duty trucks, including vans and sport utility vehicles.
* A single-speed idle exhaust test and gas cap pressure test is used for gasoline-powered heavy duty trucks and certain passenger cars and light duty vehicles that were certified by the federal government to be manufactured without OBD systems.
That is probably why the dealer is blowing you off as well. He can prove the car meets the test. In NY all they car is whether the computer says the car is good. Once you get it happy you can pretty much do what you want. As more of this starts to happen the Feds will crack down by pulling the state's highway funds and we will be back to more restrictive requirements.
It sounds like this is a used car dealer and not a GM dealership.
Bill
Two different types of tests are used in Illinois.
* An OBD test (On Board Diagnostics) is used for most 1996 and newer model year passenger cars and light duty trucks, including vans and sport utility vehicles.
* A single-speed idle exhaust test and gas cap pressure test is used for gasoline-powered heavy duty trucks and certain passenger cars and light duty vehicles that were certified by the federal government to be manufactured without OBD systems.
That is probably why the dealer is blowing you off as well. He can prove the car meets the test. In NY all they car is whether the computer says the car is good. Once you get it happy you can pretty much do what you want. As more of this starts to happen the Feds will crack down by pulling the state's highway funds and we will be back to more restrictive requirements.
It sounds like this is a used car dealer and not a GM dealership.
Bill