Clogged Cat - Flush Or Replace?
#1
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I have a clogged cat, or so says monroe mufflers.
I was having some issues with accel/gas mpg and I ended up going through several steps before discovering this. B12 in the fuel tank, oil change, trans oil change, new plugs/wires. There were small improvements but i was still lacking the accel/mpg im use to, gettin glike 20mpg atm. So i ran some Seafoam through the intake near the throttle and theres suppose to be a bunch of smoke come out the rear. Well, about as much shot me in the face as well went out the back. A friend of mine said i may have a crack or leak in my exhaust intake manifold.
Soooo, i took it into monroe muffler for free inspection and they said that the cat is clogged and that the gasket between the header and the cat is blown, because of the cat being clogged. I know the seafoam strips the gunk it has to go through the exhaust and sometimes has to be blown out in a big chunk.
I am guessing that the gasket seal thingy was bad (leaking pressure and causing loss of pwr) before i did the seafoam flush to clog the cat (if it wasnt already) so...
Do i just replace the gasket and hope to blow the cat crap out the ass?
Do i replace the cat with it right off the bat?
-if replacing cat, i would probably just get one from a salvage yard off another hyundai. or is there something else i can do besides going to the dealer?
THANKS in advance!!
I was having some issues with accel/gas mpg and I ended up going through several steps before discovering this. B12 in the fuel tank, oil change, trans oil change, new plugs/wires. There were small improvements but i was still lacking the accel/mpg im use to, gettin glike 20mpg atm. So i ran some Seafoam through the intake near the throttle and theres suppose to be a bunch of smoke come out the rear. Well, about as much shot me in the face as well went out the back. A friend of mine said i may have a crack or leak in my exhaust intake manifold.
Soooo, i took it into monroe muffler for free inspection and they said that the cat is clogged and that the gasket between the header and the cat is blown, because of the cat being clogged. I know the seafoam strips the gunk it has to go through the exhaust and sometimes has to be blown out in a big chunk.
I am guessing that the gasket seal thingy was bad (leaking pressure and causing loss of pwr) before i did the seafoam flush to clog the cat (if it wasnt already) so...
Do i just replace the gasket and hope to blow the cat crap out the ass?
Do i replace the cat with it right off the bat?
-if replacing cat, i would probably just get one from a salvage yard off another hyundai. or is there something else i can do besides going to the dealer?
THANKS in advance!!
#2
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I dont think junk yard will sell you a cat.Atleast where I live they wont.
But get a high flow universal one and have it welded on like I did.There not that expensive cheack summit or ebay.
But get a high flow universal one and have it welded on like I did.There not that expensive cheack summit or ebay.
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Replace it with an aftermarket high flow cat and enjoy the power increase!
Don't get a used one, and DON'T get it from the dealership, unless they can do it for free under warranty.
Don't get a used one, and DON'T get it from the dealership, unless they can do it for free under warranty.
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I will have to check those sites. There are no emissions test in my state so im ok with just hollowing it out if thats possible, i've heard of that being done. Just trying to keep this cheap cuz i dont have a couple/few hundred to burn right now.
and everything is OEM except my plugs/wires if that helps. thx
and everything is OEM except my plugs/wires if that helps. thx
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its possible to hollow it out, but once one goes bad the other is not far behind, i was able to hollow both the one in the header and the other down stream one, i would recommend only trying this if you are really broke and truly cant afford it because it is against the law, harmful to the environment and a biatch to do the header
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Just buy some headers, this will fix your exhaust manifold leak.
Then, buy a hi-flow cat to go right after your header, this will keep everything legal, give you a power increase, and fix your problem smile.gif.
Should be able to get the headers for like $120, the cat for like $50, and probably pay like $60 at an exhaust shop to have the cat welded in. To install the headers, follow the DIY on the site, do it yourself and save some money.
Keep in mind you will have to buy a cat that has an o2 bung in it, and extend the o2 sensor wires.
good luck!
Then, buy a hi-flow cat to go right after your header, this will keep everything legal, give you a power increase, and fix your problem smile.gif.
Should be able to get the headers for like $120, the cat for like $50, and probably pay like $60 at an exhaust shop to have the cat welded in. To install the headers, follow the DIY on the site, do it yourself and save some money.
Keep in mind you will have to buy a cat that has an o2 bung in it, and extend the o2 sensor wires.
good luck!
#7
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<div class='quotetop'>QUOTE (zoned019 @ Jul 12 2007, 04:37 PM) <{POST_SNAPBACK}></div><div class='quotemain'>Just buy some headers, this will fix your exhaust manifold leak.
Then, buy a hi-flow cat to go right after your header, this will keep everything legal, give you a power increase, and fix your problem smile.gif.
Should be able to get the headers for like $120, the cat for like $50, and probably pay like $60 at an exhaust shop to have the cat welded in. To install the headers, follow the DIY on the site, do it yourself and save some money.
Keep in mind you will have to buy a cat that has an o2 bung in it, and extend the o2 sensor wires.
good luck!</div>
is there a site you would recommend where i could get both of these pieces? i saw at summitracing they had the pre welded cat and the universal one. if having a shop do it, get the universal?
thanks again
Then, buy a hi-flow cat to go right after your header, this will keep everything legal, give you a power increase, and fix your problem smile.gif.
Should be able to get the headers for like $120, the cat for like $50, and probably pay like $60 at an exhaust shop to have the cat welded in. To install the headers, follow the DIY on the site, do it yourself and save some money.
Keep in mind you will have to buy a cat that has an o2 bung in it, and extend the o2 sensor wires.
good luck!</div>
is there a site you would recommend where i could get both of these pieces? i saw at summitracing they had the pre welded cat and the universal one. if having a shop do it, get the universal?
thanks again