Check Engine Light - PO430

[HOTLINC]

My 2000 V6 LS recently started displaying the check engine light. I put my OBD II tester on it and the code PO430 came up. It says "P0430 Catalyst System Efficiency Below Threshold (Bank 2)"

Has anyone encountered this problem, and if so - what was the solution? I've read a couple of different opinions online, but haven't found any real help.

Thanks...

[Steve L]

Slow sensing reaction of the O2 sensor past the Cat. Voltage Reaction change time is too slow.
Restriction of the cat. High coolant temperatures, rough idle are usual symptoms.
Egr valve not shutting off completely. Dumps too much combustion gases into the exhaust stream (less likely this is the problem though)

[cheerio]

I just had the same problem, so I had the O2 sensor replaced. Is this going to be a constant problem?

[HOTLINC]

Steve,

Thanks for the information. My car (knock wood) is running very well - with no symptoms that you mentioned. Smooth idle, rock-solid temp. gauge (don't know about EGR valve...) My mileage stays steady at 23-24 mpg on every fill-up.

I put a BORLA exhaust on about 4 years (60,000 miles) ago and never had an issue until this - would this cat-back exhaust have helped cause the problem? I read on the Continental page of a guy that put a Magnaflow on his and got similar codes.

Thanks for your help - I will pay attention to the temperature of the coolant/engine.

Should I do something with the EGR valve? Can/Should it be cleaned?

[LSRX101]

A large part of the time this means that the cats failing. Not always, but be prepared just in case. I've seen it caused by an overly rich fule mixture, but there were also drivability and other concerns.

[HOTLINC]

The LS has an 8 yr/80,000 miles emissions warranty - which would mean that if my convertor is bad - they should replace it. The question is whether or not they will come to that conclusion and replace it?

I have 76K now - so I'd better get cracking on it!

PS - I do my own maintenance.