Tuesday, November 18th, 2008 AT 8:36 PM
My 04 impala LS keeps showing 2 codes when a code reader is connected, 1 being P0420 and P0420(pending)i looked up the definition and it says catalyst eff. Below threshold (bank 1), this all started after a drive on the expressway home from work during a storm and the light has been on ever since so my question is does these codes mean that the converter is gone or is it sumthing I am missing as to what else may be causing these codes any things you suggest I check to remedy this would be greatly appreciated, was thinking of changing the 02 sensor but haven't been able to tell which one is the bank 1 snsor, also whenever the car accelerates there is a water swishing noise on the pass side floorboard that s constant for awhile then settles it seems after the car is driven for a prolonged amount