Opinions on cutting out catalytic converters.

[Ken B]

so lets muddy the water just a little more....whats your opinion if you live in a state with NO inspections. which way is better with Cat or without.....

 

[AuroraGirl]

so lets muddy the water just a little more....whats your opinion if you live in a state with NO inspections. which way is better with Cat or without.....

depends if yours is working fine or not or if it has one. if your vehicle has a cat, and its not plugged, I would say leave it 99% of the time. If its problematic, replace with universal if you want the fuel odor and the smells to be improved and the air qualioty part. if it dont matter, they sell pipe and clamps at the store

 

[Ken B]

I have nothing right now, looking to do duals....so 2x the cost if i put em on. maybe cheapo universals....

 

[bucket]

Working in a scrap yard i will tell you.... most people dont realize theres many different kinds of cats and values on them based on the year, material used in them, vehicles it came from and current market values and situations. There is a pay to play app called ecocat that most people use thatll give you a decent idea. Just as an idea.... the 90s gm cars that used the "bread loaf" cats usually pay pretty high, while old "bead " style cats like @Goldie Driver do not. Most people think a huge DPF filter off a diesel is big cash due to size and its almost always useless because of what its made from.

But the diesel ones are always worth looking into, just in case. I always take my converters and stuff to one place because they always pay based off of exactly what it is (like your place). I had a filter of some kind off my buddy's '08 Ram that I assumed would have no value. They looked it up and payed me almost 200 bucks for it.

 

[Goldie Driver]

so lets muddy the water just a little more....whats your opinion if you live in a state with NO inspections. which way is better with Cat or without.....

I'd say path of least resistance, but would not pay to have one installed unless required.

 

[Grit dog]

A tank of AV Gas is good for the truck (and soul) once in a while!

Agree 1000%!
But good thing not many know about it, or access to it would likely be reduced…
The 86 has been off the road for almost a year now, started the resto late last fall. After driving both tanks down to near empty, I dumped a 5ver of 100LL into each tank. Good to know that a year later I still have good fresh fuel in it.
Actually I should freshen it up. Getting low.
The old 74 Jeep gets 100LL when it’s going to sit for a long time, as does all my small engines. Slightly more costly than fuel stabilizer, but hard to beat fuel with a 2 year shelf life!
No bueno for cats though!

 

[SirRobyn0]

so lets muddy the water just a little more....whats your opinion if you live in a state with NO inspections. which way is better with Cat or without.....

See my previous pro and con below. But IMO I cannot see a really good reason not to run a cat. I suppose I could add if your running a built motor and your running it rich, your probably not going to be able to run a cat because there will be to much unburned fuel in the exhaust for it to handle. I'll also add that if your still running a pellet type cat, then replacing it with a universal modern cat would be beneficial.

I think and I'm not picking on anyone here, but I think the biggest reason guys don't run cat or don't want to run cat is lack of understanding or being cheap. Back in the 70's with the pellet type cats there were lots of issues and some people still carry that, either remembering an experience or word of mouth. Or someone had a problem with a 20 or 30 year old cat with lots of miles on it. Well everything has a life expectancy you know and has to be replaced eventually. And lets face it on a dual exhaust system a pair of cats can add $200 or more to the cost of an exhaust system, so back to being cheap.

Catalytic converter pros:
Cleans up your exhaust, means less smell and better for the environment.
Exhaust has a gas in it called NOx NOx dissipates quickly and is not a long term environmental hazard, however it is really good at destroying lung tissue. If your sitting in traffic or working on your truck and your smelling your exhaust you can bet your breathing that in. Ask an mechanic with COPD how he got it. probably from that and / or smoking.
Your exhaust system will last longer with a cat because there will be less acidic deposits in the muffler and pipes.
Modern catalytic converters create such little back pressure that it cannot be detected on a backpressure test.
Acts somewhat like a resonator and will mellow the tone of the exhaust somewhat.


Catalytic converter cons:
Depending on converter installed it may create a small amount of restriction
Cost money to install

So for the above reasons I have a catalytic converter on my square and also on my 77 Cadillac.

 

[Goldie Driver]

See my previous pro and con below. But IMO I cannot see a really good reason not to run a cat. I suppose I could add if your running a built motor and your running it rich, your probably not going to be able to run a cat because there will be to much unburned fuel in the exhaust for it to handle. I'll also add that if your still running a pellet type cat, then replacing it with a universal modern cat would be beneficial.

I think and I'm not picking on anyone here, but I think the biggest reason guys don't run cat or don't want to run cat is lack of understanding or being cheap. Back in the 70's with the pellet type cats there were lots of issues and some people still carry that, either remembering an experience or word of mouth. Or someone had a problem with a 20 or 30 year old cat with lots of miles on it. Well everything has a life expectancy you know and has to be replaced eventually. And lets face it on a dual exhaust system a pair of cats can add $200 or more to the cost of an exhaust system, so back to being cheap.

And, the old cats caused acid rain. Is that worse than lead in the air ?
Hard to say.

I dont believe in removing them on newer stuff, but would never spend a dime to reinstall one on Goldie.

Yes, I am cheap, but I also dont care about having one back now that its gone.

Also "lost" several back in the day for true duals.



I recycle - just ran a small truckload of cardboard to the city location and do care for the most part about the environment.

I also think for a long time that this was BS shoved down our throats and the automakers did what they had to without the technology that exists today which allows for peaceful coexistence of performance and emmissions.

But, CELs for random glitches do not help - oh, say, like how a lot of 97s would get a EVAP system leak light as they got older for no real reason.

It is nice that Goldie will never have a CEL. You have to do things the old way - watch the gauges, the exhaust, and listen for weird sounds.



My .02 from growing up in the power starved emmissions era knowing that older vehicles used to have ballz.

YMMV

 

[Ellie Niner]

so lets muddy the water just a little more....whats your opinion if you live in a state with NO inspections. which way is better with Cat or without.....

I'm at that bridge right now, as the universal cats I installed with my dual exhaust back in 2003 aren't working up to ***** anymore (common issue with cheap universal cats, as they skimp on precious metals). I live near an area with emissions regs, but have always been able to sideskirt having to test by maintaining an address outside of testing zones. I'm actually planning on buying new converters as money allows, as I like the notion of cleaner exhaust... even if I go out of my way to refuse to submit for the official emissions test.

And yeah. I do have access to an exhaust sniffer on occasion, generally used for tuning purposes.

 

[Salty Crusty]

I guess those of us in the wide open areas with no emissions testing take that for granted.
I don't remember when the last time was that a tech even looked under one of my vehicles during the inspection process. Horn, lights, brakes are what they're most concerned about.

 

[AuroraGirl]

I guess those of us in the wide open areas with no emissions testing take that for granted.
I don't remember when the last time was that a tech even looked under one of my vehicles during the inspection process. Horn, lights, brakes are what they're most concerned about.

Ha you have an inspection process. unless its salvage title being "reprocessed" or whatever, needing the state law enforcement to inspect it before proceding with removing the block from registering , there is no such thing you speak of remotely possible in my DMV life. maybe some thing medium duty / commercial but not regular ol class.. d..? Nadddda. yayyy. Plus horns are iffy around here anyway.

 

[AyWoSch Motors]

No such thing as any form of inspection here, thank God. Nothing I own would ever pass if we did. You'd be amazed at the things I see driving on the road here.
If you have a windshield and taillights, you pretty much good.

 

[AuroraGirl]

No such thing as any form of inspection here, thank God. Nothing I own would ever pass if we did. You'd be amazed at the things I see driving on the road here.
If you have a windshield and taillights, you pretty much good.

IS THAT A CRACK IN YOUR WINDSHIELD I SEE? Fix it ticket. not to me ive never been given one but I know someone who is dilligent and their windshield cracked and they had an appt for a new one and they got a ticket for it in a span of like days and then i know people who drive around with soemthing i imagine only glue is holding from falling out or shattering and never have. crazy. I have one windshield with a crack where someone took a tool and instead of leaving it(started at outside edge of windshield horizontally) they ran a scribe in a gentle u turn and ran it to the side 2 inches down. I imagine that is for relief if it ever wanted to continue it doesnt spear across 3/4 of the windshield in eye line and then finish down by the wiper or roof?

 

[AuroraGirl]

And, the old cats caused acid rain. Is that worse than lead in the air ?
Hard to say.

I dont believe in removing them on newer stuff, but would never spend a dime to reinstall one on Goldie.

Yes, I am cheap, but I also dont care about having one back now that its gone.

Also "lost" several back in the day for true duals.



I recycle - just ran a small truckload of cardboard to the city location and do care for the most part about the environment.

I also think for a long time that this was BS shoved down our throats and the automakers did what they had to without the technology that exists today which allows for peaceful coexistence of performance and emmissions.

But, CELs for random glitches do not help - oh, say, like how a lot of 97s would get a EVAP system leak light as they got older for no real reason.

It is nice that Goldie will never have a CEL. You have to do things the old way - watch the gauges, the exhaust, and listen for weird sounds.



My .02 from growing up in the power starved emmissions era knowing that older vehicles used to have ballz.

YMMV

97 was a 3800 gm car by chance? OR newer truck? Or something not-ford by chance? GM rolled out enhanced evaporative systems for hte most part by 98 at final line to receive them but they were pretty aggressive and if a model changed in the 96-99 range they pretty much got the updooted stuff which the whole point was it was more complex yes but it also had a lot more diagnostics aids and was less dumb so you couldnt smell gas and never have a code, basically.(This existed alongside obd2 stuff but wasnt apart of it except for the IM monitors)

The reason why is P0443 is a ***** and old cars do tend to get it but you would prob fix it with either a new gas cap, any leaky line fixed, fuel pressure regulator, fuel pump o ring, or purge valves. if it was temperature dependant almost exclusively the rubber sealing of those parts only or the diagnostic shraeder port was uncapped or filler neck clamps as well. If it was dependent on a level in tank it would oftenm be the canister or vent valve or the piping for these. or a electrical issue that wasnt detected enough by the PCM on the 5v ref circuit where it could pull low or high on the fuel tank pressure sensor , skew the reading but not bump engine sensors enough that was illlogical to operating conditions and (Sometimes) it could be bad enough to wacky wednesday the whole car and it wouldnt throw a code for that sensor but it would say 5 volt ref. So the diagnostic test of checking for pressure bleed off in a calibrated time and monitoring fill and startup temps / driving behavior etc etc you could get a code to not come back for 8 months. my po443 is almost entirely temperature related except one day in summer but i had a not done my fuel pump yet(gauge would bob around if it Hit a spot near center and this put a new o ring on which may have been why. Because of that and no gas smell, I send it and just delete the code when it happens. usually in -40 and cruising.

Also note the engine coolant sensor and intake air sensor can be used for the test criteria and the sensors shifting but still not enough to make them run bad can also cause this issue because the car will have different expectations of the pressure drop rate when performing its seal and watch test on the tank. Colder temps would see much less pressure build in the tank(i think they do build and drop to test different parts, either technically can cause the code at least in my car because each car has a programmed understanding of at what __ will __ do ___ and its extensive. Its actually a huge reason GM had to change computers to be more beefy and have more computing HP because of the evaporative emissions expanding hugely.

 

[Goldie Driver]

97 was a 3800 gm car by chance? OR newer truck? Or something not-ford by chance? GM rolled out enhanced evaporative systems for hte most part by 98 at final line to receive them but they were pretty aggressive and if a model changed in the 96-99 range they pretty much got the updooted stuff which the whole point was it was more complex yes but it also had a lot more diagnostics aids and was less dumb so you couldnt smell gas and never have a code, basically.(This existed alongside obd2 stuff but wasnt apart of it except for the IM monitors)

The reason why is P0443 is a ***** and old cars do tend to get it but you would prob fix it with either a new gas cap, any leaky line fixed, fuel pressure regulator, fuel pump o ring, or purge valves. if it was temperature dependant almost exclusively the rubber sealing of those parts only or the diagnostic shraeder port was uncapped or filler neck clamps as well. If it was dependent on a level in tank it would oftenm be the canister or vent valve or the piping for these. or a electrical issue that wasnt detected enough by the PCM on the 5v ref circuit where it could pull low or high on the fuel tank pressure sensor , skew the reading but not bump engine sensors enough that was illlogical to operating conditions and (Sometimes) it could be bad enough to wacky wednesday the whole car and it wouldnt throw a code for that sensor but it would say 5 volt ref. So the diagnostic test of checking for pressure bleed off in a calibrated time and monitoring fill and startup temps / driving behavior etc etc you could get a code to not come back for 8 months. my po443 is almost entirely temperature related except one day in summer but i had a not done my fuel pump yet(gauge would bob around if it Hit a spot near center and this put a new o ring on which may have been why. Because of that and no gas smell, I send it and just delete the code when it happens. usually in -40 and cruising.

Also note the engine coolant sensor and intake air sensor can be used for the test criteria and the sensors shifting but still not enough to make them run bad can also cause this issue because the car will have different expectations of the pressure drop rate when performing its seal and watch test on the tank. Colder temps would see much less pressure build in the tank(i think they do build and drop to test different parts, either technically can cause the code at least in my car because each car has a programmed understanding of at what __ will __ do ___ and its extensive. Its actually a huge reason GM had to change computers to be more beefy and have more computing HP because of the evaporative emissions expanding hugely.

This was a 97 Isuzu Rodeo, and in doing research at the time - maybe mid to late 2000's - it seemed like a common issue across the makes. Buddy had a 97 GMC small blazer - S15? and had EGR problems. Apparently they hit a certain age and it basically amounted to non stop emmissions issues.

Both of the check engine lights on the Camaro were emmissions related. Bad air pump check valve, and the electric air pump.

Replaced the fuel pump and sender in the wifes Ranger - maybe 6 months later starting getting CELs. Chinesium sender was hanging up and instead of just giving BS fuel level readings it triggered the code. Apparently the test of the fuel vapor system ties in to the fuel level.

OBDII was designed to not only monitor faults, but predict them. It does that all too well.

The Cobalt throws a code in the winter because the commanded temp by the thermostat is different than what it is seeing.

The tranny in my Moms car messed up recently- CEL. Nice that it gave codes, but shouldn't there be a TEL or PEL vs a CEL for that ?

It is the way of the modern automotive world, and in some ways having a scanner tell you where to look is nice, but to me it seems like the emmissions stuff is what causes the most trouble if like me you drive older vehicles that are computer controlled.

I also despise push button start - give me a key.

Infotainment systems? Eff that - a simple radio with a tape player or CD is plenty.

Not sure they even put CDs in car radios anymore. They expect you will download music from your phone.

Wow - it's a phone. Designed to make and receive calls, and, oh yeah, vent about tech on a web based old truck forum ...