ZachCouch Posted May 12, 2018 Share Posted May 12, 2018 I've been swapping the headers and up-pipe on my Outback XT today. When I got to the point that I needed to take the downpipe off to access the up-pipe studs, I discovered there's no catalytic converter in my downpipe, but there should be. There aren't any signs that it's been removed, it looks like it just wasn't ever there in the first place. I've been getting a P0420 code ever since I bought the car (~2 months ago), so it looks like I've found the cause. I suppose it's just degraded and has been blown out the back. I haven't had any problems (other than the emissions code) as a result of the missing cat, but now I'm concerned, and I don't want to blow up my engine. I've been wanting to order an Accessport anyways. Will one of their OTS maps work with a gutted stock downpipe and a catted mid-pipe until I can order a proper downpipe to replace them? In the mean time, will I do any damage if I drive my car to work so long as I stay out of boost? Link to comment Share on other sites More sharing options...
xtea Posted May 13, 2018 Share Posted May 13, 2018 Can you post a picture? This makes no sense. Stay out of boost for sure. Link to comment Share on other sites More sharing options...
relative4 Posted May 13, 2018 Share Posted May 13, 2018 Yes, please post a pic of that downpipe. A stock downpipe consists of 2 sections, each with a cat. If they'd been gutted, you'd know it. If you have an aftermarket catless downpipe and a factory tune, you'd have much bigger problems than a P0420. So some research on what tune you actually have may be the next step. Link to comment Share on other sites More sharing options...
ZachCouch Posted May 13, 2018 Author Share Posted May 13, 2018 Sorry, now that I go back and read it, my post is a little hard to follow. Here's the downpipe, removed from my Outback: And here's what it looks like on the inside: It's a Subaru OEM downpipe, but there's not a catalytic converter in it. Tomorrow I'll remove the other section of the downpipe (which I thought was called the mid-pipe), and see if that cat is also missing. Like I said, it hasn't been giving me any trouble other than the P0420 code (which only comes on during highway trips). Link to comment Share on other sites More sharing options...
madrig Posted May 13, 2018 Share Posted May 13, 2018 Link to comment Share on other sites More sharing options...
xtea Posted May 13, 2018 Share Posted May 13, 2018 So that’s not gutted? Perhaps if you removed the heat shield you may see a weld job. Link to comment Share on other sites More sharing options...
relative4 Posted May 13, 2018 Share Posted May 13, 2018 OK, so the upstream half of the factory downpipe has been gutted. I have heard of people gutting just one of those two cats; I don't remember the details. If the downstream half still has the cat, it should be harmless if you stay out of boost, but don't delay in getting the AP and a downpipe to fit one of the OTS tunes. Stock downpipe, aftermarket catted downpipe, either way according to your performance goals and emissions requirements. If you post a WTB in the marketplace forum here or NASIOC, and search the marketplace forums, craigslist, etc., you can probably find a good used factory DP. Link to comment Share on other sites More sharing options...
ZachCouch Posted May 13, 2018 Author Share Posted May 13, 2018 I'll check the other cat tomorrow, hopefully it's still in there. Is it likely that I harmed my engine by boosting with this exhaust setup? I've only had this car a couple of months. I haven't taken it WOT yet, but I've done plenty of backroads driving. I wanted to get a Cobb catted downpipe anyways, but I wanted to wait a little while and set some money aside for it. I guess I'll just have to put in some overtime and get the parts. Is it worth looking for a used Accessport? Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.