it seems like my check engine light keeps coming on when it's raining...it doesnt' go away, i have to clear it. but i'm getting a p0420 and also, can't remember the number but it's for a slow ckt response on o2. could the o2 be getting wet and thus cooling it down too much to get a good reading? also someone suggested that my ecu might be getting too wet and is causing problems. when i check my i/m monitors it says everything is ready and reading right. but i'm getting those 2 codes? any ideas? i have a 2 1/4 exhaust with a pacesetter and homebrewed cai

Best guess: The downstream O2 sensor has a bad connection and water is getting in there.

so maybe it's just not tight enough.... could i maybe have to relocate the bung? it's a custom exhaust, so maybe it's just wrong?