Hi yall...

My brother has a 99 civic LX-- the CEL was on and the code pulled was a bad O2 sensor. I was changing out the sensor and saw that the header was cracked-- I"m thinking that this may have something to do w/ the faulty 02 sensor readings. I'm thinking that I should replace the manifold first before I replace the sensor, just to make sure I'm fixing the problem and not the symptom.

A couple of questions:

1. Is that manifold welded onto the cat? It looked like it was from my short exam of it.

2. I found a place that well sell me an aftermarket OEM equivalent (both mani and cat) -- I don't think it CARB exempt (i'm in California)-- for about $275. I think that's a pretty good price. However, the results I'm pulling up online give me non-carb exempt combos for roughly the same price, and the CARB certified ones are about $500+. Will it make a difference? I want to make sure it passes SMOG.

Any ideas?

thanks in advance for your help!

 

bump

anyone?

 

it should be bolted to the cat, i beleive. i have an 04 so i cant speak for you, someone here will tell me if im wrong though

and you can get an aftermarket header from megan racing for mid 100's

 

i have the same problem mines look cracked too the thing is that i got a new one but i have the stock Exhaust the think is that i dont want to weld it i want to get the exhaust

 

with the LX, the cat comes after the header. I say get a new header (megan or DC), and a high-flow cat (magnaflow or randomstech) to go right behind it. The exhaust is only as free-flowing as the most constrictive compnent of the exhaust system. There is a big possibility the cracked header has something to do with the fault o2 reading.