'Emergency' Catalytic Converter Trouble Code Fix

Messages
19,479
Location
Chicago Area
For those who may wish to run a catless car and get no codes, or who have a bad cat code thrown [engine light] because the second O2 sensor is not reading differently from the first, here is a fix. There are $80 electronic adapters that go in series with the second O2, but they don't always work and are expensive. So: http://forums.evolutionm.net/1505717-post2.html This is simply using 2 18mm spark plug anti foulers stacked. Then the second O2 is simply screwed in. This lets the sensor 'see' less exhaust, and usually works to stop the code, and maybe get through an emissions test. Am I a horrible polluter and criminal? I have sympathy for those who can not afford $500-$1,400 to get a cat welded in, and need their cars to survive.
 
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Messages
1,385
Location
Houston, TX
Both methods work great, especially if your emissions testing is just the OBDII plug-in and no tailpipe sniffer. I have a Catalytic Converter (Rear) code that popped up as soon as I replaced my front O2 sensor...the old rear O2 was not reading as quickly nor as accurately as my new front O2. Unfortunately the above mods only work with a functioning rear O2.
 
Messages
10,060
Location
Central Washington
It can be done with wiring as well. It worked on my Cavalier for at least a year. http://colt45.ws/misc/02sensor_wiring.jpg My Vic started rattling a cat at 29k. So I took it to the dealer. They called me up with some outrageous price quote. So I went down there and smacked them around a bit with my knowledge. Turned out no one in the front knew about the extended emissions warranty. Just kept preaching "3/36k." I made them talk to the higher-ups who confirmed it was covered along with several Techs who walked through.
 
Messages
3,402
Location
Iowa
 Originally Posted By: mechtech2
Am I a horrible polluter and criminal?
No, because the new laws don't take into account inflation has made us all poorer. I replace my wife's cat last year with an aftermarket that is spec'd for the car, but the dam light comes on anyway. I need this fix. Thanks much for posting!
 
Messages
4,837
Location
Kansas
 Originally Posted By: mechtech2
Am I a horrible polluter and criminal?
I have seen a few owners scrap their perfectly good car because they could not afford the $1400 cat fix. In my book, you are not a criminal at all.
 
Messages
2,260
Location
NY, NY
WOW!! That's cool. When I hear of people spending over a thousand dollars for cats, I can't believe it. I recently had to replace the dual cat assembly on my truck since I was getting a light and four new O2 sensors didn't fix it. (two front, two rear) I got the Walker assembly from the manifolds to the muffler for 425 dollars. I paid 60 each for four Bosch 02 sensors. The guy who inspects my truck every year swapped out the pipe for 100 bucks. My CEL is out since the repair. These cats are a little smaller than the factory cats, so we'll see how long they last.
 
Messages
4,837
Location
Kansas
 Originally Posted By: NYEngineer
These cats are a little smaller than the factory cats, so we'll see how long they last.
If you live in California, there lies the problem. You have to get your replacement from the factory.
 
Messages
14,727
Location
Santa Barbara, CA
 Originally Posted By: Kruse
 Originally Posted By: NYEngineer
These cats are a little smaller than the factory cats, so we'll see how long they last.
If you live in California, there lies the problem. You have to get your replacement from the factory.
bingo, even OBD1 have to have OEM cats now, universal fit are illegal to install and are not supposed to pass visual.
 
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25,045
Location
ON, Canada eh?
 Originally Posted By: bdcardinal
 Originally Posted By: Kruse
 Originally Posted By: NYEngineer
These cats are a little smaller than the factory cats, so we'll see how long they last.
If you live in California, there lies the problem. You have to get your replacement from the factory.
bingo, even OBD1 have to have OEM cats now, universal fit are illegal to install and are not supposed to pass visual.
Why does it matter if it works? These CARB people need to get a life! \:\!
 
Messages
14,727
Location
Santa Barbara, CA
 Originally Posted By: StevieC
Why does it matter if it works? These CARB people need to get a life! \:\!
meh im not complaining, although most of the OBD1 cats from Ford are obsolete. the problem with the universal ones is that they only work for a year or so. they are really poorly made and are the one pass cat type. that being said, i had an offroad X pipe on my 98 mustang, no cats. ive been contemplating putting a offroad downpipe on the Volvo. you can turn the catalyst monitor off with a tuner, so you dont need to do the non fouler trick.
 
Messages
35,998
Location
ME
 Originally Posted By: StevieC
These CARB people need to get a life! \:\!
Well if it doesn't have an expensive CARB # it's not supporting the CARB "goodfellas" and they might wither and die. There are lots of apps with crossmembers in the way, or where mud on the cat doesn't look out of place. Wonder how Nevada border exhaust shops are doing businesswise.
 
Messages
4,837
Location
Kansas
 Originally Posted By: bdcardinal
meh im not complaining, although most of the OBD1 cats from Ford are obsolete. the problem with the universal ones is that they only work for a year or so.
I know what the solution is in my state. But what is the solution in yours? Let's just say somebody brings in a 1978 Mercury Zephyr that needs a new cat. This part has long been discontinued by Ford. Aftermarkets are out of the question. Besides sell the vehicle to somebody out of state, what do you do?
 
Messages
1,346
Location
Texas
Gotta love the anti-fouler trick. I've helped several people do it to their cars and recommended it to several others. Way better than going electrical around exhaust works.
 

JHZR2

Staff member
Messages
44,841
Location
New Jersey
In NJ, there is an exemption if you spend over $500. I made the mistake of using a $200 special catalytic converter once to pass NOx. The converter only worked marginally better than the broken OEM one, and when I put in the OE cat two years later, emissions were squeeky clean. Some would probably call you a criminal for doing that mod... some would call the prices for the emissions equipment criminal. I don't think that being "poor" is a pass for emitting more pollution or bypassing the laws. They still ought to put forth a good faith effort to remediate the issue.
 
Messages
2,097
Location
kansastan
 Originally Posted By: mechtech2
For those who may wish to run a catless car and get no codes, or who have a bad cat code thrown [engine light] because the second O2 sensor is not reading differently from the first, here is a fix. There are $80 electronic adapters that go in series with the second O2, but they don't always work and are expensive. So: http://forums.evolutionm.net/1505717-post2.html This is simply using 2 18mm spark plug anti foulers stacked. Then the second O2 is simply screwed in. This lets the sensor 'see' less exhaust, and usually works to stop the code, and maybe get through an emissions test. Am I a horrible polluter and criminal? I have sympathy for those who can not afford $500-$1,400 to get a cat welded in, and need their cars to survive.
Great tip... food for thought. It's a non-issue here in Kansastan, but I've lived in other states where this sort of thing was an issue.
 Originally Posted By: Solo2driver
Both methods work great, especially if your emissions testing is just the OBDII plug-in and no tailpipe sniffer. I have a Catalytic Converter (Rear) code that popped up as soon as I replaced my front O2 sensor...the old rear O2 was not reading as quickly nor as accurately as my new front O2. Unfortunately the above mods only work with a functioning rear O2.
That's odd, as it's pretty much the opposite of what I've seen. This um... friend of mine... had a '96 Olds Achieva a few years ago with a hollowed-out catalytic converter. It was throwing codes for the downstream oxygen sensor for obvious reasons. This *friend* of mine replaced the upstream sensor, leaving the old downstream sensor in place. The code went away and never returned. Could have been a fluke, but it worked at least once.
 

mechtech2

Thread starter
Messages
19,479
Location
Chicago Area
Yes, the anti fouler mod requires operating O2 sensors, fore and aft. But it is aimed at bad cats and their resultant trouble codes, not O2 sensors. The $ shock value of a cat far exceeds that of a mere O2 sensor, which is easily replaced.
 
Messages
588
Location
Chicago, IL
 Originally Posted By: JHZR2
In NJ, there is an exemption if you spend over $500. I made the mistake of using a $200 special catalytic converter once to pass NOx. The converter only worked marginally better than the broken OEM one, and when I put in the OE cat two years later, emissions were squeeky clean. Some would probably call you a criminal for doing that mod... some would call the prices for the emissions equipment criminal. I don't think that being "poor" is a pass for emitting more pollution or bypassing the laws. They still ought to put forth a good faith effort to remediate the issue.
Agreed. Not a criminal, but definitely slightly irresponsible. Especially if the car is in such a state of bad tune that it is wrecking cats. Just look at the sky in any big city on a warm windless day and see the effects of pollution. It is not good for us.
 

NJC

Messages
3,007
Location
Vancouver BC
 Originally Posted By: mechtech2
Am I a horrible polluter and criminal?
Emission's testing can be a heaving PITA. Especially since it doesn't take in to consideration the qty of miles driven.
 

mechtech2

Thread starter
Messages
19,479
Location
Chicago Area
Anyone else ever consider the massive waste of fuel and added pollution of the EPA system? I have to drive my car almost 20 miles to the nearest station - one way! Let's multiply that by all the cars, at varying distances. Just to tell me the engine light is not on and it's OK. And remember, they won't let you get license plates if the car does not pass!
 
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