P0420 Code??!!
#1
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P0420 Code??!!
Hey my intercooler piping fell off a couple weeks ago. This has happened before. The car would throw a code, then it would disappear... but not this time.
Now its throwing
P0420 Catalyst efficiency below threshold
I tried to reset this a few times and it keeps coming back.
I dont have a test pipe. Most of the time i see these codes on the forums its for a test pipe.
So is my cat bad, or one of my o2's?
thanks.
Now its throwing
P0420 Catalyst efficiency below threshold
I tried to reset this a few times and it keeps coming back.
I dont have a test pipe. Most of the time i see these codes on the forums its for a test pipe.
So is my cat bad, or one of my o2's?
thanks.
#2
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do you have a cel eliminator ? tried a antifouler thingy? i had a similar issue on my oz not a evo but related in the trouble code
http://www.obd-codes.com/p0420
on mine my precat is failing and the its integrated into the header....
does it always comback after a reset? or does it take awhile for itto reappear?
imthinkin if its always ther after u clear it then somthin maybe bad ie o2 sensors
http://www.obd-codes.com/p0420
on mine my precat is failing and the its integrated into the header....
does it always comback after a reset? or does it take awhile for itto reappear?
imthinkin if its always ther after u clear it then somthin maybe bad ie o2 sensors
#5
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Even a hi-flow cat can cause a P0420. I cleared it about four times, but it kept coming back. I finally installed an anti-fouler adapter on the o2 sensor, cleared the code, and that fixed the problem. On my 2004 Evo, I had to use the 90 degree type because a straight fitting jammed the o2 wires into the body pan. Probably depends on the brand of exhaust you have.
#6
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I dont have a test pipe. The code will go away once i reset it... but if i get it on it immediately, the code comes back on. I dont know if its my cat or an 02, or how i can determine which it is.
#7
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http://www.autozone.com/autozone/par...h?sortType=low
they have ones that have a 1yr warr on them but those cost more.
im in same boat as you, luckly i dont have to worry about it untill my smogg is due next april.. btw, how does the car drive? just curious if a bad cat causes a problem.
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#9
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so am i better off paying off someone to diagnose the problem to figure it out? how do i tell if its the cat or one of the 02's? i want to fix it so i can sell the car.
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