skizix Posted February 27, 2007 Share Posted February 27, 2007 Ok, looks like it's time for a new cat for my '02 OBW (2.5). Got the 420 code, occasional sulphur smell (not lately though), ocasional burning metallic smell (more lately), rattles a bit (front cat) when I whack it (could that be just the heat shield?), and intermittent hesitation on takeoff (no major revving issues otherwise though) despite eliminating nearly all hez-inducing possibilities (except knock sensor, but I'm told that would not be intermittent), and some other tough-to-otherwise-explain minor intermittent driveability issues. So...what cat to get? Usually, I'm pretty strict about going with OEM replacement parts. But best I can find on an OEM cat is around $500 shipped. Aftermarket cats are *so* much cheaper. Being a non-turbo, I don't really want to mess with flow/backpressure too much. And I'd rather get a direct-fit, rather than deal with welding anything. Definitely need to pass emissions, and really would like to see my CEL extinguish and stay that way. Would of course like to see the replacement cat last for a good while. So then, what is a good aftermarket cat for a 2002 2.5l outback? The one I've been eyeing is an Eastern Catalytic, for around $250 shipped. Is that a decent product? Anybody have any other rec's for an aftermarket cat? Or am I best off sucking it up and plunking down for the OEM cat? Quote Link to comment Share on other sites More sharing options...
bkcraun Posted February 27, 2007 Share Posted February 27, 2007 Go to your local muffler shop and have them weld in a universal cat. You can probably get it done for less than $150 total. Quote Link to comment Share on other sites More sharing options...
nipper Posted February 27, 2007 Share Posted February 27, 2007 how about a persian? someone had to say it. http://www.catalyticconverter.net/ www.jcwhitney.com thats where i get mine when i have to. nipper Quote Link to comment Share on other sites More sharing options...
Badgerman Posted February 27, 2007 Share Posted February 27, 2007 Check with your dealer…………my wife had a cat replaced under (extended?) warranty on her 2000 2.5L OBW. I can’t remember the details but her car produced the same 0420 code. BTW, the cat replacement did not fix her drivability/hesitation problems but new O2 sensors did. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted February 27, 2007 Share Posted February 27, 2007 the 95 - 99 legacys and outbacks are known to throw a code for the cat when it really is the front o2 sensor that needs to be replaced. if you get a new cat your're probably going to get the new o2 sensor as well. i'd try the sensor first. lots cheaper. Quote Link to comment Share on other sites More sharing options...
cookie Posted February 27, 2007 Share Posted February 27, 2007 It's been a few years and I think it cost $60 for the ox sensor when mine got PO420. Two places told me cats. I'd sure try the ox sensor first since they time out at about 100,000 miles anyway. Quote Link to comment Share on other sites More sharing options...
nipper Posted February 27, 2007 Share Posted February 27, 2007 You do have all the symptons of a failed cat. You should replace the o2 sensor first, as you should get a new one with a new cat anyway. The smell isnt so much a red flag, but the rattling when you whack it with your hand is. How many miles are on this car? nipper Quote Link to comment Share on other sites More sharing options...
skizix Posted February 28, 2007 Author Share Posted February 28, 2007 Ok, can't reply from work, but now I'm back. Car has 117k miles on it, and it's a 5MT. I replaced the front o2 sensor with an OEM unit around 12k miles ago. Last time it was in the shop, I even had 'em temporarily replace the new front o2 with a known good one -- no difference. So front o2 is good. Haven't replaced the rear. I bought a universal for the rear, but haven't gotten around to it yet. Rear o2 could be causing my 420 code, but I doubt it, since I've smelled the rotten eggs and the cat rattles (slightly, muffled) when I smack it. Other things I've done to look into the hesitation/driveability: new plugs, wires, replaced coil with a very clean looking used one ($50), air filter, swapped out MAP sensor, checked for intake and exhaust leaks (none). Ran a can of BG44K in the tank. Ran seafoam into intake. None of those have made a noticeable difference. Nice, clean, used IAC ($50), which did solve my low speed bucking issues, but not hesitation. Have not tried knock sensor, but I'm told that would not cause intermittent problems, but steady. Could a chunky cat be causing intermittent hesitation on takeoff, occasional "stepped" acceleration and deceleration, and once in a while a lurch when I let off the gas suddenly? Shop said my exhaust tested good for not being obstructed, but if stuff is rattling around in the cat, seems like it could occasionally become partially obstructed temporarily. Power seems good (except when hesitating), and revving high is not a problem. One clue: the hesitation does not seem to occur before the engine gets up to running temp (i.e. when in open loop mode). Also, resetting the ECU seems to help things for a day or two (tough to be sure on those, since symptoms are intermittent). Those makes it sound like a bad front o2, but as above...checked/fixed that. Makes it sound *not* like knock sensor. Little confusing. Any other ideas? BTW, as for the cat being maybe fried...when I bought the car (100k miles), it had a bad neutral switch (no ECU, but realtime scan revealed it). Replacing that improved driveability for sure. Not exactly sure what the neutral switch does on a manual tranny, but presumeably it affects engine management -- maybe was running chronically rich and killed the kitty? BTW, bad neutral switch prevented CEL from checking cat efficiency (says that is the case, right in the factory manual), and not coincidentally, it threw that code for the first time right after I replaced it. Anyhow, thanks for the feedback. Sounds like I can avoid shelling out for the OEM cat, which is good news. I suppose I'll try changing the rear o2 first, but I really doubt it's going to help w/ CEL or driveability, given the other evidence. No opinions on Eastern Catalytic's quality? So again: do you think if my cat's bad (but not totally clogged), could it be causing hesitation, etc.? Quote Link to comment Share on other sites More sharing options...
skizix Posted February 28, 2007 Author Share Posted February 28, 2007 http://www.catalyticconverter.net/ www.jcwhitney.com thats where i get mine when i have to. nipper Whitney does not have a direct-fit for any subaru. catalyticconverter.net has suby ones, but not one for a 2002 leg/OB (they have up to '01 legacy). ecatalyticconverters.com and ebay have the Eastern Catalytic unit. Any other sourcing ideas? Quote Link to comment Share on other sites More sharing options...
nipper Posted February 28, 2007 Share Posted February 28, 2007 It sounds like its your cat. you have all the symptons. The second o2 sensor is just a check against the first, it has no effect on emissions (interestingly my car just threw a code for the downstream o2 sensor). The stumble, the timing of it all fits. nipper Quote Link to comment Share on other sites More sharing options...
JohnVT Posted February 28, 2007 Share Posted February 28, 2007 It sounds like its your cat. you have all the symptons. The second o2 sensor is just a check against the first, it has no effect on emissions (interestingly my car just threw a code for the downstream o2 sensor). The stumble, the timing of it all fits. nipper my car threw a code for the downstream sensor a few weeks ago... of course, I'm doing the t-belt thing this week instead. will you change just one sensor? both? thanks Quote Link to comment Share on other sites More sharing options...
nipper Posted February 28, 2007 Share Posted February 28, 2007 My front sensor is 6-8 months old, so i wont change that. My front threw the ocassional code, then got worse with time, so i included it as part of a major tune-up. nipper Quote Link to comment Share on other sites More sharing options...
mrCharlie Posted February 28, 2007 Share Posted February 28, 2007 ..when I bought the car (100k miles), it had a bad neutral switch (no ECU, but realtime scan revealed it). Replacing that improved driveability for sure. Not exactly sure what the neutral switch does on a manual tranny, but presumeably it affects engine management -- Couldn't agree more about how much that switch seems to actually do. I had a persistent stalling problem as well as tons of bucking and other odd drivability issues that drove me crazy for months until I replaced the switch. Best $20 I've spent on my car. Quote Link to comment Share on other sites More sharing options...
cookie Posted February 28, 2007 Share Posted February 28, 2007 Yep, if you've changed the sensor and have a rotten egg smell and rattles... In Hayward CA there was a place that rebuilt cats, not sure if they are still there. That's what I put on my last car and it was still going several years later. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.