so i noticed that my engine pretty much cuts out at like 5600rpm...instead of running like a monster all the way to the redline like it usually does. after noticing this problem, a CEL got thrown and my buddy scanned it...and this is what i got...

P0420 Catalyst System Low Efficiency ECM, PCM

does anybody know what this means? i'm taking it to the dealer within the next couple days, seems as how is less than a year old...but i would love to know what's wrong with it in advance. my car only has 8600 miles on it. can anyone shed some light on this?

 

i've got the same code. cat is clogged, or possibly the air is not getting through it to the sensor behind it due to a problem like this one:

 

cat is probably clogged up...going to need a new one.

 

ok cool...cat is clogged...why the bogging down at high rpm's though? is the air not able to escape quick enough and is causing too much back pressure?

 

high RPM = high exhaust flow.
think of it like a pinched hose, and your turning the tap on full bore.

 

pretty much.....the cats have been known to go bad in these cars as well.

 

sweet. this would be a perfect opportunity to finish off my exhaust with a CA header and XTC downpipe...but my mom is being lame and not letting me spend money. oh well...guess i'll just buy my motorcycle and hide it from her in my buddy's garage :P

i'll just take it to the dealer and have a new stocker put in for now. come to think of it...i slipped up and used no-name premium gas a couple times...probably why my cat clogged. oh well...i'll just make a mental note to ONLY use BP, Mobil, or SHELL only from now on...i really do notice a power difference in my car now...i miss my little beast.