Dam SES light

12-24-2004, 11:50 AM

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Dam SES light

I keep getting "DTC P0420 Catalyst System Low Efficiency"

Could it be a bad cat or would O2 sims take care of this for me?
I have 2000 SS with stock manifolds, cats, SLP y-pipe and magnaflow muffler.Help

12-24-2004, 11:57 AM

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Friend of mine had the same code a few months ago, dealer replaced his driver's side cat for free under the U.S. 8yr/80K federal emissions warranty.

12-24-2004, 06:39 PM

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low efficiency? why does the system have ANY efficiency. screw cats- get rid of them...