NA cat rattle - Kill the cat?

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realfinn
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NA cat rattle - Kill the cat?

Post by realfinn »

Well I noticed a nice rattle coming from my cat. Aparantly the element has finally turned to gravel. What do you guys think about running a NA engine catless? Will it CEL all the time (like my last car did) or fowel plugs (again like my last car did)? What will be the negative effects?
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Splinter
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Post by Splinter »

How did running catless foul your plugs?
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realfinn
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Post by realfinn »

According to the GM guy when the car was run without the cat the decrease in back pressure effected the O2 readings. The O2 sensor made the fuel map crazy and I ran it like that. It started fouling plugs about every 10K. I guess the early GM ECU's were pretty picky. The CEL came on right after I gutted the cat. Everything went to hell in a hand bag after that.
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Legacy777
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Post by Legacy777 »

I don't see how not running a cat on a subaru could cause the plugs to foul.
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206er
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Post by 206er »

when i was running catless it did run slightly rich and I am pretty sure the o2 sensor was good.
1994 Touring Wagon: ruby mica, 5mt swapped
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555BCTurbo
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Post by 555BCTurbo »

206er wrote:when i was running catless it did run slightly rich and I am pretty sure the o2 sensor was good.
It may smell a bit richer, but that is just because the cat isn't there to filter out the particulates and hydrocarbons that it normally would...


Catless works fine...go for it!
Nick

1987 Audi 4000CS quattro...soon to be 20VT
1994 Dodge Ram 2500 4x4 CTD, #11 plate, 30 psi, Scotty II intake, 4" exhaust
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turboleg
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Post by turboleg »

Will it be noticeably louder?

I noticed on my EJ22T it got louder when I ran the gutted cat.
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SubiePrice88
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Post by SubiePrice88 »

My N/A just started to do the same rattle, I was wondering the same thing.
-Jordan

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evolutionmovement
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Post by evolutionmovement »

Are you sure it's internal and not just the heat shield? That can be fixed with two large band clamps from Home Depot.
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