Catalytic converter

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I noticed that once in a while my car hesitates, also the exhaust smells bad, both of these things occur but not all the time. my one friend said that the cat might be plugged. Is there a way to check this? and what if I just put a straigt pipe in there will that affect anything? As for emmisions I just got my car e-tested several months ago and never has to be done again because it will be 20 years old.

posted by  jarvisx2000

Also is it possible my car has 2 cats? because thats what it looks like, or is that something else?

posted by  jarvisx2000

Well what kind of car is it? And if your talking about full straight pipes, its illegal. Fords used to use 2 cats on some of their cars and Dodge did with a few, but if its Chevy then it shouldnt have 2 cats.

posted by  car_crazy89

straight pipes arent illegal it illegal on car before 90's but the 80's and the 70's straight pipes are completly legal

posted by  google.com

Well i think/thought around here atleast they are cause the sound (noise violation).

posted by  car_crazy89

it is against federal law to bypass the catalytic converter on anything that was originally equipped with one (or more).

posted by  dodger65

If the car's 25 years or older, you can do whatever you want to it. Even if it did have a catalytic converter or not.

posted by  Juhosaphat

can you supply any proof of that?

posted by  dodger65

Ya i agree with you Dodger, i have never heard of that rule/law before. Why else do people think cars 25 or older still have their exhaust instead of straight pipes or cut off at the header.

posted by  car_crazy89

i'm thinking he means that, where he's at, they stop testing emissions at 25 years, so your chances of getting caught are lower if you have a 25 y.o. car. what i'm saying is that, as far as federal law is concerned, any emissions equipment it had from the factory had better be there (on a street licensed car) when the feds come to your house and open your hood (yeah, right) or they'll fine the crap out of you. (once again--yeah, right) it's not like they really enforce it, but it's there...

posted by  dodger65

Unless the engine in the car is not original and I think they give variances for modified or alt-fuel, if you can pay for the variance.

posted by  srober32

I am not sure if you guys are grasping maybe a concept of straight from manifold to muffler pipe? That does keep the noise pollution down and is legal in most states as long as you don't need an emissions test done. Most cats ive seen do nothing for noise pollution but mufflers do. Also I have yet to see any negative effects in any of my vehicles. And all six are set up this way. It also will give you a couple of more hp.

posted by  staceymommy

I am pretty sure it is illegal to run a straight pipe here if the car originally came with a cat, but I dont think they will be checking an 86 accord to see if I still have the cat on it, now if you pull the plug on the cat and all of those little beads fall out, is that the same as a straight pipe?

posted by  jarvisx2000

a) yes, i think we're clear on what they're talking about.
b) the function of a cat is not to remove noise.
c) no, removing a cat. is not legal. if you don't have to pass emissions, that doesn't mean it doesn't legally have to be there. it just means that the likelyhood of getting caught went down substantially.
d) performance gains will really only be had by eliminating a pellet style converter. the monolithic (honeycomb) really have almost no effect on performance...

posted by  dodger65

All I did with mine is I cut the pipe at both ends of the cat and then welded a pipe where the cat was. If you cut the pipe close enough to the cat you shouldn't have any beads and should have enough clearance to get a good weld.

posted by  staceymommy

Still not legal, no matter what. Anyone can say its good and its ok to do but wait until your caught, your mind would change. It is easier and cheaper to just take it off (wont have to replace it) but in the long run it could cost you a lot more if you happen to be caught. I have to stick with what Dodger is saying.

posted by  car_crazy89

I also agree, the fine for removing emissions controls is something like $100,000 for a shop and Lord knows how much for individuals, I don't have that kind of money. It is less "your car needs to be tested" than "we are cleaning up the environment".

posted by  srober32

of course if the guts were to "mysteriously fall out" of the converter, the automobile owner might not be aware of it... :hi:

posted by  dodger65

Umm, well officer the car was in the shop for awhile, maybe they wanted to have a little fun or maybe got bored? I had no idea it was missing. :screwy:

posted by  car_crazy89

Driver; Yes, officer, there is not a cat there, but we are testing to see if the cat was the problem.
Officer; Why is it rusty, then?
Driver; I don't know, old pipe?
Officer; Here's your ticket. Drive safely.
Driver; :doh:

posted by  srober32

If that scenereo happened, the emmissions testing officer will fail the car and give you thirty days to either get it fixed or park the car until it gets fixed.

Regardless if testing is done or not, it it illegal to modify the emmissions control system on a car and cause the car not to meet the emmissions standards for its the model year - period. - In the Tennessee counties where we have testing, the testing applies to any car 1975 or newer.

In most states, you can get a waiver - if you can show you spent a certain amount of money (usually about $400) on the car after it failed emmissions and still failed to comply. This waiver is a year to year thing.

posted by  tbaxleyjr

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