rcross5

So about a month ago i started experiences a decrease in power of of start, almost as if the engine was bogging down. I would putt the pedal to the floor and the engine would engage, and jump foreword till up to higher gears. It would also idle really terribly and a few times shut off on me at a red light. Went to have my codes red and got P0420 Cat code and that one of the O2 sensor were bad. I changed the Cat and both 02 sensors as of yesterday, and the problem seems to be alleviated. About halfway to work this morning the check engine light came back on though, and on the way home the problems re-ensued. Any ideas what could be causing this?

Poopies

iTrader: (4)

Did you try an idle relearn?
Have you taken your idle air control (IAC) valve off and cleaned it?
How's your coolant looking? Mine ran like crap when my head gasket was leaking. It even backfired a few times!

Wankenstein

Here's a similar thread: http://mechanics.stackexchange.com/q...reshold-bank-1

(copy and pasted from another site): "I'm having the same issue - Check Engine light is on, giving me a P0420 code. Pulled off heat shield and have a crack almost all the way around the exhaust manifold. I'm patching it temporarily until I can get a new manifold/cat put in - thank god I'm a DIY or that could get expensive! I, too, wonder why Honda hasn't issued a recall for this problem. It's happened in plenty of their cars (over several models) and it strikes me as a poor design, and possibly even poor materials."

Did you purchase OEM (Denso) A/F sensors?

Colin42

What kind of cat did you put in?
These cars don't usually like cheap cats

ezone

You have brand new codes, what are they?