DTC CODE P0420 (KOOKS HEADERS & HI-FLOW CATS )
#1
Burning Brakes
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DTC CODE P0420 (KOOKS HEADERS & HI-FLOW CATS )
I have been getting DTC P0420 (TWC system low efficiency bank 1-A), for the second time since installing headers and hi-flow cats. The repair manual refers to the cats. I notice that both times it has happen I was in stop n go traffic. I have cleared the code and did not returned until yesterday. I have drove the vette over 800 miles, since the first code, and another 1000 miles (C5 bash and back), since getting the first code. Is it possible one of the cats is bad, or do I need to get it tuned? I have checked all the fittings for leaks, and everything seems fine. I am trying to wait until I do the cam swap this fall. The car runs fine, other than having that code pop up again. Anyone else have this problem? Thanks :confused:
#2
Le Mans Master
Re: DTC CODE P0420 (DNAST1)
I have the same code on the other bank P0430 and they said it could be weak o2s or just the nature of the high flow cats. You can edit it out if you want to w/ an ECM editing software.
dave
dave