[4th Gen : 01-07]: P0420 code
#1
P0420 code
Hi guys I just installed a new muffler on my '03 Caravan (160,000) miles and everything was fine until about 350 miles and I got the P0420 code.Catalyst efficiency low-bank 1. I double checked for leaks in the exhaust but everything is tight. Any ideas on this? I installed a Walker direct fit replacement muffler
Thanks
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