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How do I eliminate pre cat

1K views 2 replies 3 participants last post by  Cdn17Sport6MT 
#1 ·
So CEL been on for good six months plus, for the pre cat, cat integrated in manifold. Which is causing I believe horrible gas mileage and miss.
I do not want to spend $900-1400 to replace, since I plan on trading the car in, in near future and will have dealership deal with it/and smog lol.
So I am wondering what would it take to eliminate that dam precat cheaply, and I mean cheap as possible, and will if affect the car or cause it loose power. I have read it's the start up cat, and it's what computer reads for air fuel mixture etc. So if I somehow can cut cat off add pipe to extend down to resistor, it is possible would cause issues or make CEL stay on.

Or do I need to look at going a different route or buying different headers with a cat?

Help please??!!?? I've never seen anything like this, and I disgusted with the design, and price to replace :cry::cry::eek::eek::mad::mad:
 
#2 ·
The primary or "pre-cat" is built into the exhaust manifold/header. You would have to purchase or weld up a whole new header/manifold in order to eliminate the cat. I would not recommend just cutting the secondary cat off and leaving it be, you need the O2 sensors to go somewhere as well so if you do just cut the cat off and weld a pipe in make sure there is a bung on the new pipe for the O2 sensor.
 
#3 · (Edited)
To the OP, the design of the four-into-one header pipe and compactly integrated pre-cat - though a person would wish were modular (separately replaceable) - is one of the features of Skyactiv, and which allows the car to run 13:1 compression on regular fuel, giving some decent gas mileage compared to its peers. I'm surprised that the replacement cost is as cheap as you say, given its design.

This was one of my concerns prior to buying the car... but your info tells me that despite its complexity it's relatively speaking cheap to replace.
 
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