Catalytic Converter - Yes or No?

[BuddhaRock]

I have a 2002 Buick Regal LS. Acceleration has been very poor on it for the past few weeks and it has been drinking gas and oil like water. I took it to the shop and they said it's because the catalytic converter is clogged. They are charging almost $500 to fix it.

I've been told by some people that I can just replace the cat with a pipe and it would be a lot cheaper AND improve power, but have also heard that this is a bad idea and can actually be illegal. Sadly, no one is able to give me good insight. Besides googling it, can you guys offer any advice? Should I save the money and have someone take out the cat or should I shell out the money and do it the way the shop wants to?

 

[sneakypete123]

Cats are harmfull to engines and make your vehicle use more fuel as they restrict flow and your engine has to work harder as a result.
Removing your cat will improve the gas flow, use less fuel and increase power (slightly)

As for the law? Not sure how it works over the pond but in the UK any vehicle over 3yrs old has to under go an MOT test once a year which includes an emissions test, if the car was built with a cat it needs to be in place during the test, although its not a major job to reinstall it once a year.

 

[TheBook]

Do it the way the shop wants to. If you don't have a cat, you will fail any emissions test and can be charged a pretty hefty fine for not having one. You can get around it by having the shop put a high-flow cat on, but honestly, on a vehicle such as yours, I'd just have them slap an OE unit on and call it a day. Not having a cat will improve power over an OE one, but you don't have a race car so I wouldn't worry about it.

 

[Beeblebrox237]

Replace the catlaytic converter. It's the law.

 

[xXKingJoshXx]

I've been told by some people that I can just replace the cat with a pipe and it would be a lot cheaper AND improve power, but have also heard that this is a bad idea and can actually be illegal.

I don't really recommend it. It is illegal here in Indiana to remove your catalytic converter, but many places will do it anyways.

Do it the way the shop wants to. If you don't have a cat, you will fail any emissions test and can be charged a pretty hefty fine for not having one.

We don't have emissions testing in Indiana, but if you are found out, yes, you can be fined.

And like you said, if you or the shop is positive it is the cat, just go with an OE part. Unless you're really struggling for money, I would definitely not recommend a straight pipe. (Even then I don't know that I'd recommend it)

 

[sneakypete123]

The whole concept of a cat is flawed. They are supposed to absorb harmful gasses thus helping the enviroment ..... but it makes your engine burn more irreplaceable fossil fuel :/
Wheres the sense in that?

 

[FordMKIVJ5]

The whole concept of a cat is flawed. They are supposed to absorb harmful gasses thus helping the enviroment ..... but it makes your engine burn more irreplaceable fossil fuel :/
Wheres the sense in that?

It converts CO (carbon monoxide) into CO2 (carbon dioxide), unburnt hydrocarbons to CO2 and H2O and nitrogen oxides into nitrogen and oxygen.

Carbon monoxide is highly poisonous and nitrogen oxides form ozone in the troposphere (again poisonous). So what it does is removes everything that's poisonous and converts it into something that causes global warming. Not at all pointless as I see it.

 

[sneakypete123]

But when you weigh up the energy it takes to get the precious metals such as platinum and iridium that are used in them plus the fact of the extra fuel its using.

Dont forget the fact that it takes 20 + mins of driving for the cat to heat up enough to even start working and lots of peoples journeys are shorter than that.

IMO they do more harm than good

 

[motortrend]

But when you weigh up the energy it takes to get the precious metals such as platinum and iridium that are used in them plus the fact of the extra fuel its using.

Dont forget the fact that it takes 20 + mins of driving for the cat to heat up enough to even start working and lots of peoples journeys are shorter than that.

IMO they do more harm than good

In The E9x M3 at least there Is a ~30sec cat warmup, don't know if other modern cars do this as well.

TBH I don't care much for cats, I'll probably have the primaries removed when the car is mine. I mean, who doesn't want extra power and sound

 

[niky]

A clogged cat will typically be a symptom of oil consumption, not the cause. Beyond replacing it, you need to find out the primary cause of your engine's oil-o-holic ways.

 

[BuddhaRock]

Thanks for the suggestions, everyone. I am going to bite the bullet and just get it replaced. I have no intention to break the law, even if it does mean getting better performance.

 

[CAMAROBOY69]

Depends on the state. You don't "have" to have a catalytic converter in all states. I would recommend removing and bypassing it. But that is your call depending on the state you live in. Magnaflow makes a catalytic converter that is legal and is a straight through pipe. And yes it will increase your hp and improve gas mileage in most vehicles. A guy I work with has almost the exact same year Regal as you and he bypassed his with the magnaflow I suggested.

 

[McLaren]

Depends on the state. You don't "have" to have a catalytic converter in all states. I would recommend removing and bypassing it. But that is your call depending on the state you live in. Magnaflow makes a catalytic converter that is legal and is a straight through pipe. And yes it will increase your hp and improve gas mileage in most vehicles. A guy I work with has almost the exact same year Regal as you and he bypassed his with the magnaflow I suggested.

Nearly every car comes with a catalytic converter these days & removing any OEM converter is considered a Federal offense across every state. The misconception that it depends on the state is due to some not having any emissions testing or sniffer tests. All that means is that they don't check for the converter, not that it still isn't regarded as an offense if you're the one caught removing it. Most shops won't even consider it due to the $10,000 fine associated with it.

What your friend has is still illegal in the eyes of the law, unfortunately, because chances are what your friend bought has a statement somewhere that says, "For off-road use only" to save Magnaflow's butt.

 

[Anna+Reece]

What Camaroboy said is right.

In Minnesota, you don't need a cat. There are no emissions here, no testing or smogging or inspection or anything. I don't think there is in Indiana either. So you could just bypass it, and you would be fine. Replace it with a stock cat or a test pipe.

 

[Badasp5.0]

Mclaren is right about removing it and the legal ramifactions of it. What that being said I have yet to have issues not running cats on my Mustangs over the last 15 years.

 

[McLaren]

What Camaroboy said is right.

In Minnesota, you don't need a cat. There are no emissions here, no testing or smogging or inspection or anything. I don't think there is in Indiana either. So you could just bypass it, and you would be fine. Replace it with a stock cat or a test pipe.

No testing doesn't change anything. It just means you don't test for emissions.
http://www.epa.gov/otaq/cert/factshts/catcvrts.pdf

WHAT YOU SHOULD KNOW ABOUT USING, INSTALLING, OR
BUYING AFTERMARKET CATALYTIC CONVERTERS


As of January 1, 1988, all persons engaged in the business of automotive service and repair, as well as other parties named in section 203(a)(3) of the Clean Air Act*, are prohibited from installing or selling aftermarket catalytic converters which have not met the criteria of EPA's interim enforcement policy entitled 'Sale and Use of Aftermarket Catalytic Converters'* (published on August 5, 1986). The installation of non-complying converters by a named party will be considered a violation of section 203(a)(3) of the Clean Air Act, and the violator may be subject to a civil penalty of up to $25,000 for each improper installation

-4-
(6) When can I install an aftermarket converter?
Generally, there are only 3 situations when you can install an aftermarket converter.
They are:
(1) if the converter is missing from the vehicle when brought in for exhaust system repair; or
(2) if a State or local inspection program has determined the existing converter has been lead poisoned, damaged, or otherwise needs replacement; or
(3) if the vehicle is more than 5 years old or has more than 50,000 miles*
(8 years/80,000 miles for 1995 and newer vehicles) and a legitimate need for
replacement has been established and appropriately documented (e.g., a
plugged converter or unrepairable exhaust leaks).

(11) What may happen if I don't use the correct converter?
First, it is a violation of Federal law because it is likely to increase the amount of pollution coming out of the vehicle. Penalties for violations by individuals, service or repair shops or fleet operators are up to $2,500 per violation. (Each improper installation is considered a violation.) New car dealers can be penalized up to $25,000 per violation. Any person who causes a violation could be subject to the same penalty as the installer.

 

[SRV2LOW4ME]

A clogged cat will typically be a symptom of oil consumption, not the cause. Beyond replacing it, you need to find out the primary cause of your engine's oil-o-holic ways.

This.

 

[homeforsummer]

Dont forget the fact that it takes 20 + mins of driving for the cat to heat up enough to even start working and lots of peoples journeys are shorter than that.

That depends on the car (and rather precludes your use of the word "fact"). Most modern cars place the cat a lot closer to the engine, which warms them up quicker (and protects them from theft rather better too). Can be as little as a few minutes in the best modern vehicles. Really, cats are only a hindrance on older, often carburetted vehicles, rather than modern, precisely-controlled injection ones.

That said, there is an argument that the very cleanest modern cars are getting to the point where catalytic converters aren't actually necessary any more. I believe Honda's current generation of hybrids is particularly efficient in combustion to the point that many of the harmful gases are negligible anyway.

 

[BuddhaRock]

My car is running like new after the replacement. Thanks for steering me in the right direction, folks.

 

[White & Nerdy]

May I just say, anyone who actually thinks an aftermarket cat sould be blanket illegal is a jerk?

I mean seriously, what's the point. Emissions testing & approval organizations do exist, so just let them handle it. Better yet, just let the existing I/M tests handle it.

Also, does that mean any car that comes with a cat has to use the stock cat forever, even once it's past the 25-year (35 in most parts of California) "we don't care anymore" threshold?

 

[CodeRedR51]

My opinion: does the car require emissions tests for registration?

Yes - replace the catalytic converter.

No - do whatever you want, even if it means replacing it with a straight pipe.

$500 sounds like a rip off anyway, get a second opinion on the install.

Edit: missed the installed post, sorry.

 

[Slash]

From what I understand, under law it has to be there if the vehicle came equipped with it, unless it is older than 1996 (1996 was the introduction of the current OBDII emission isnpections), or until it is 26 years after the model year of the vehicle, of which then emissions inspections are obsolete (emissions inspections are obsolete if the vehicle is newer than 2 years also). This is New York law, but I'd imagine it would be pretty similar elsewhere.

In short it has to be there on your car.

 

[White & Nerdy]

Also, since the Sunbird hasn't hit the 25 year mark yet, and I can't imagine the factory single cat/single exhaust setup being very good for performance, does anyone know if it's technically legal to intentionally ruin a catalytic converter so I have an excuse for using a dual low-restriction cat/dual exhaust setup?

 

[Slash]

Also, since the Sunbird hasn't hit the 25 year mark yet, and I can't imagine the factory single cat/single exhaust setup being very good for performance, does anyone know if it's technically legal to intentionally ruin a catalytic converter so I have an excuse for using a dual low-restriction cat/dual exhaust setup?

You can't legally gut a cat, but people do. You're better off running a high flow aftermarket cat if that's what you want, but prepare to pay a pretty penny. Technology has come a long way since that car was made, so cats flow very well now than they did then, especially factory cats. Enough to the point people use them on drag cars to keep them street legal. They do still hinder performance but not to the level they used to. Basically it's gotten to the point now where having a cat isn't really an issue.

As far as your question, no, you can't legally take it out or modify it in anyway if it is in working condition, the only exception being if the rest of the system is in need of replacement. The only way you can replace it is with something aftermarket that qualifies as a factory replacement, which usually these come in high flow anyways. Usually it will tell you if it qualifies on the box, online in the ad, or from the mechanic in a shop, before you purchase it.

 

[McLaren]

Also, since the Sunbird hasn't hit the 25 year mark yet, and I can't imagine the factory single cat/single exhaust setup being very good for performance, does anyone know if it's technically legal to intentionally ruin a catalytic converter so I have an excuse for using a dual low-restriction cat/dual exhaust setup?

It's not legal. Tampering with the setup is still against federal law.

 

[White & Nerdy]

It's not legal. Tampering with the setup is still against federal law.

So... true dual exhaust is blanket illegal on any car that come with a single pipe or Y-pipe setup from the factory and any sort of low-restriction setup is blanked illegal on ANYTHING that came with a converter.

WHAT THE 🤬 is the EPA thinking?

 

[Slash]

No. It's not illegal to have a dual exhaust system on a vehicle that came with a single or y pipe, as long as it has the necessary emissions equipment, like cats and 02 sensors etc.

For example, forgetting the fact the my truck is emissions exempt because of age now, it had a single flow pipe on it with a cat. This was factory installed with the 4.9L straight 6 engine it originally had. I could have converted it to a dual exhaust setup but it would have needed cats. I don't believe it had O2 sensors as it was an OBDI vehicle not OBDII. Regardless the ECU was cut out but that's besides the point.

When we did the V8 conversion, the exhaust setup had to have, you guessed it, cats, because the truck had them originally. It would not pass state inspection without them. It still has high flow aftermarket ones on it now, but they aren't required anymore because of the age. It's now a classic vehicle.

 

[Joey D]

WHAT THE 🤬 is the EPA thinking?

Probably that people don't want to be inundated with smog.

 

[White & Nerdy]

Probably that people don't want to be inundated with smog.

I was thinking more along the lines of outlawing all non-factory cat setups, including ones that allow better fuel economy without creating excessive smog.

Same logic that leads the California Air Resources Board to outlaw a lot of cold air intakes, probably.

 

[Slash]

I was thinking more along the lines of outlawing all non-factory cat setups, including ones that allow better fuel economy without creating excessive smog.

Nope everything is quite legal as long as it has a cat, then you are good.