1997 Accord SE, 4 Cylinder Automatic, NON VTEC. 220,000 Miles.

Issue - CEL - Code p0420 - Bank 1

Cat and 2nd O2 sensor are original. Front O2 sensor (by radiator if I remember?) I replaced about 2 years ago.

There is a lot of rattling coming from the CAT and while I don't know for sure, I highly suspect it is shot. It's just a giant ball of rust.

While I would really like to use Honda parts, they are just too expensive and I need to try and do this myself to save money. The closest O'Reilly autoparts has a bolt on Magnaflow for $189 with a 5 year warranty. Autozone has a Magnaflow universal bolt on for $90 with a 2 year warranty. I read guys were having to replace/repair them not too long after putting them on initially. Was this one certain brand or what? I can't find where I read that but I was almost sure it was on here.

From what Ive read/been told the hardest part of this whole deal will be getting the old bolts off. lol Other then that, does anyone have any advice? Baring a lemon, are these aftermarket cats garbage or what? Is this an "easy" repair?

Thanks for the feedback.

 

Some aftermkt. cats are JUNK I know OEM stuff is very costley so ask first!!!

 

Here are some pics of what my set up looks like. The cat has some JB Weld on it to close up a few exhaust holes.

If anyone has any advice on how to get that second O2 sensor I'd appreciate it. I don't even know what tool to use to get that freakin thing off. lol

 

A couple of months ago I replaced my cat with a Walker Direct Fit 16067 due to a P0420 CEL. $100 shipped free from Amazon with a $40 rebate. I don't know if the rebate is still valid. I had to cut the back bolts off with a torch and I had to heat the O2 sensor with a torch to get it off. The threads on the sensor didn't look too good but it screwed in OK, doesn't leak, and no more CEL. The cat itself fit fine on the stock hangers.

From the pics, it looks like your rear pipe flange is rusted away, not the cat, but maybe I'm not seeing it.

 

Yea with the rust and "stuff" on the rear, you might want to replace that pipe along with the cat.....I'd unplug the O2 and drop it with the pipe. Once on the ground you can decide to re-use the old O2 or replace it.

 

Thanks for your reply. Removing it all, That is the plan as of now. I figure even if the sensor isn't technically bad, it's got 220,000 miles on it so I'm ok with replacing it. If memory serves these Hondas are a pretty sensitive bunch with the O2 sensors correct? I forget where I bought the front one but I had to order that brand online.

Do you happen to know if the cats you typically get from the auto stores (like magnaflow) are decent or am I going to be replacing them every 6 months?

Thanks for the replies guys!

 

Most are good and come with a warranty...be sure to read the requirements of the warranty......most "defects" are caused by other issues....like a bad O2 dumping too much fuel.

 

OK, well I replaced the front O2 sensor with a denso and just ordered the same for the rear sensor so I should be ok. From what I've read on here Denso is the brand to get for o2. Thanks for the help!

 

Anytime...let us know how it goes.

 

here's a good video on how to check your catalytic converter:

How to check your vehicle's catalytic converter. - YouTube