M-benz

The CEL is pop up so I went to Autozone to scan it ..the P0420 is the code that they gave me . The guy told me its 02 sensor but I don't know is it the upstream ( primary ) or the downstream ( underneath the car ) or maybe because of my CAT ? Can someone help please ?

deving916

iTrader: (2)

I had this code in a 00 civic ex one time.

Do you have the cat on there still?

M-benz

Everything is still intact so how did u solve urs ?

HondaPartsHero

Check for exhaust leaks before or in the cat. Otherwise generally its a bad cat.

M-benz

Hmm ok so it's not O2 sensors at all ?

TheRealTegger

No. Oxygen sensor problems would prompt different error codes.

Check for exhaust leaks, as directed before. If none, then the cat has deteriorated below the threshold that the engine's computer is programmed to consider acceptable.

One thing that dramatically reduces cat life is to allow the car to run out of gas, or to drive around with a very-low gas tank level. Honda warns about this in later Owner's Manuals.

UGAVtech

It's an inefficiency code, this might help...

TheRealTegger

If that really worked, don't you think somebody other than Scotty Kilmer would have picked it up by now?

thewrai6th

Standard code for bad catalytic converter. Can be caused by o2 sensor, but unlikely. If the Pri or Sec O2 sensor is bad, it will normally set off the code for a bad sensor.

Just an FYI, if you burn a lot of oil, plan on replacing it again within a couple years. I got sick of dealing with P0420 and got an O2 extender, but that won't work if you're trying to pass smog.

M-benz

Lets just if the CAT was bad ..what do I need to get replace with ? OEM Honda one ? Man I bet it would be pricey . Any other brand that you can guys recommend ? I kinda still confused when the code says bank 1 but its not necessary mean O2 sensors hmm ... How do I check the CAT to know if its bad or not ? We don't have smog check here so can I just run w/o CAT but the CEL is still on ?

M-benz

You lost me buddy

thewrai6th

http://bigdaddiesgarage.com/angled-cel-fix-real.html

TunerN00b

Any legal cat will do.

No.

What is there to be confused about? If you don't understand what a catalytic converter does, or how it's performance is monitored, then stop wasting time on here and take it to a professional.

First, with a visual inspection. Followed by using a pair of wideband O2 sensors if need be.

If you're willing to break the law (doesn't matter if you have a smog check or not, it is a federal requirement) and don't care about either the environment or anyone around you, and don't care that you will be giving up your early warning for engine issues (CEL becomes useless when always on), and are ok with the increase in volume and raspiness of the exhaust from using a test pipe instead of a cat, then yes. Otherwise, just put a working cat on the damn thing.

M-benz

Yes sir lol

edc056394

Just had the same code replaced the cat and no more light

M-benz

May I ask what type of cat did u replaced if u don't mind I'm asking or maybe a part # so I can order one ?

M-benz

What do you guys normally replace with ? Maybe a part # would help ...

tamboo

these fit 95, probably some others. search your model to double check.

http://www.rockauto.com/catalog/x,ca...,parttype,5808

or if you have a large bank account:

http://www.acuraoemparts.com/delray/...RA__CONVERTER#

M-benz

I found this on eBay ...what do u guys think ? It should fit w/o any modification according to their description !!!

http://item.mobileweb.ebay.com/viewi...d=170471587691

tamboo

looks too brand x imho.
personally i'd spend a bit more for the eastern catalytic model
since it has the little <3 next to it = most purchased.
they could be made by the same chinese factory tho, who knows.

http://www.rockauto.com/catalog/more...972&cc=1000382