Where is the best place to find an OEM exhaust system? I found mitsubishiparts.com but they sell the front pipe, cat, intermediate pipe, and muffler all seperate. It comes out to like $1k, which I dont really want to part with right now. Ill have to get a pic of my current exhaust but the muffler is at an angle so just a stock muffler wont fly. I already checked Ebay and the sale/buy threads here...any help is appreciated.

 

gotta love oregon. Thats all i have to say.

 

Here is what i would do. Just buy the stock muffler, then go to an exhaust shop and have them make the rest of the piping for you.

 

Have you EGR checked, the front o2. Make sure the TPS is good or it may send the ECU wrong throttle position info, make sure your air filter is clean....I can't think of anything else that may make your emissions faulty, other than a high flow cat. I say that because, you failed the lower speeds and not the higher. I don't think it's the exhaust, I think it's something to do with the sensors and EGR.

Oh and don't forget to check the vacuum lines going to the EGR and just check them all for cracks and whatnot.

 

Does your motor ping? Does it feel like it's slower than it used to be? If so, then I would say it's the sensors and/or EGR system. If not, then I would say that the cat is bad. Have you put racing gas in your car? If not, the previous owner may have and leaded gas can ruin cat converters. Here's some good reading about understanding the EGR system.

 

Whew thanks for the info, at least I dont have to swap the entire exhaust system. I replaced the TPS with a new one and installed it within specs awhile ago and that made a huge difference. The car idled and accelerated a lot smoother. It lowered the amount of emissions but barely not low enough. Ill probably replace the O2 Sensor too since its cheap and ill take a 2nd look at the EGR system. Im pretty sure the EGR is ok but you never know. As far as the exhaust...do you think I might be able to replace my current Cat with a stock one and leave the rest alone?

As far as race gas...its possible they put some in. I did try that Guaranteed to Pass smog stuff but that made it worse lol. My readings more than doubled, I thought I researched that stuff but apparently not enough. Looks like either way the Cat could be the factor too.