P0420 Error Code 00 civic

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Kanned

Kanned

Beast
Keeping it short, I have the P0420(Catalyst System Efficiency Below Threshold) error code locked into my 2000 Civic LX. I've tried resetting, but it returns shortly after. The engine has only 4k miles on it, but the rest of the car has about 100k. Maybe I messed up the timing.

You can read about the error here: OBD-II Trouble Code: P0420 Catalyst System Efficiency Below Threshold (Bank 1)

Symptoms include:
-Stinky white smoke
-Surges during acceleration/idle
-AC on = SLUGGISH! Have to stay down an entire gear basically.

The front 02 sensor wires are spliced, so I'll check up on that first. Other than that it will be a bunch of testing, but hopefully I can get some sort of help from all of you =).
 
Well, I can see the surging being an 02 sensor and possibly why the AC makes it sluggish, but what about the white smoke? To be honest, I don't remember if I even have a cat, I'll go check soon. Been really busy lately. If anything, what could cause white smoke besides burning oil/coolant?
 
I didn't read the whole post for some reason, you def need a cat, the surging is because the cat is clogged, what happens is the material gets burnt and breaks loose, then it clogs up the rest of the cat with the debris.
I have seen it a hundred times on the odysseys and accord v6, this will be the first time on a 4cyl, that I have seen anyway.
Usually white smoke is Gas (very very rich) or coolant, but in this case it's prolly just the cat.
 
So I finally checked under my car after forgetting whether or not I have a cat and I don't... An interesting fact that I forgot to mention is that the car does very well before it's warmed up, so it may be the heated O2 sensor. Anyhow, I'm going to swap out the sensors asap which leads me to another question... Anyone have feedback on the universal sensors found at Napa and other auto stores? Hopefully it's just one of the sensors and I won't have to worry about a cat.

Thanks,
Sean
 
universal sensors are great if you know how to wire, and I don't mean twisting them and using electrical tape, I mean solder and shrink tube.
The reason it has to be done with the solder and shrink tube is because it will be exposed to the elements and you want the connections to stay clean and intact, soldering them makes them strong and always a good connection, and the shrink tube will keep anything from getting on the wire and corroding it.
I am very good with wiring stuff like that, but when it comes to the o2 sensor I always go with bosch or ntk, and I always buy the direct fit, it's a little more expensive, but you won't have to worry about it.
 
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