Precat on the outs?

[ProZach626]

So for about 6 months now sometimes my car has had a minor fart smell every once in a while... you know, the smell of a cat going out. About a month ago I noticed my idle on my car isn't 100% steady and kinda jumps around from 600-900 (estimated) instead of holding 700rmps. Also i'm not 100% on this but the car seems a little sluggish and when I go balls to the wall (WOT) or mantain a high speed for a while I smell a slight sulfer smell even while i'm moving which leads me to believe my precat is going out. Also my gas mileage is dwindling. I'm pretty sure the thing is about out but i'm asking for a little 411. (nismo pilot don't fail me now! hehe) 1st off, does it sound like a cat failure? The bottom line is i'm flat broke so in order to replace this cat am I going to have to replace the whole exhaust manifold? How long can I drive the car like this before doing irreversable damage to my engine? I'd like to drive it easy, save up for a couple months, and buy a hotshot header and just do away with the whole precat idea. I'll probably have to wait until tax return season to fix it. Also, how much would I have to spend to fix this if I were just trying to fix precat and not go with the header? Also, will I know when the cat really bites the dust or is it pretty much screwing me over right now?

[nismo_pilot]

you could always pull your stock header and gut the precat, then youve got a ghetto hotshot header until you can get the real thing, if it comes down to it ive got my stocker i pulled off of mine i could ship you if you pay the shipping......DO NOT GO WOT UNTIL YOU REPLACE THE HEADER, corroded particulate matter can be sucked back into your engine causing scoring of the cylinder walls, get it fixed asap, you can beat the cat material out of the stock header with a broom handle and once youve got everything out of there you blow compressed air through it to completely clean it, hope this helps

[slideways...]

the only thing is that you might lose a few hp if you gut your cat. best case is equal hp, but its well worth it for the engine durability. nissan just dropped the ball on putting cats into sentras this time around.

[ProZach626]

So is it pretty easy to hollow it out? How much time does it take and will I really lose HP? My friend did it to his focus(not precat) and he actually gained HP. Also, will this trigger any check engine lights or anything?

[nismo_pilot]

it will cause your check engine light to come on, same as going aftermarket, i havent heard anything about losing horsepower although slideways may have me on this one, i havent heard anything as far as gains or losses are concerned, but its just a temporary fix until you get your hotshot anyways so i think you can live with the 5hp or so drop even if there is one...... depending on how rough you are it could take as little as 10 minutes i would assume, but i always err on the side of catuion, id spend at least 2 hours with it to make sure nothing is left floating in there......goodluck bro, as always hit me up if you need anything

[slideways...]

the hp loss is because modern cats flow well enough that you really only lose a couple hp by having them in, but hollowing it out gives a widened area that air goes in and causes turbulence, and this equals more backpressure. depending on how clogged the cat is, and how restrictive it is stock, you may not lose as much or lose more, or even gain 1 or 2. did your buddy dyno his car before and after gutting his cat? ive never heard of it actually gaining power.


oh and your CE light wont always come on, but id count on it. i gutted the cat on my old sentra before i got a high flow + exhaust(like 10 months later), and no CE light, but no power either, only noise. i was surprised that there was no CE light because it was a 1999 SR20DE with 2 oxygen sensors...

[ProZach626]

so even when I get my hotshot my CE light will come on? How can I get rid of this because here you will fail emissions no matter what if your CE light is on?

[nismo_pilot]

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