hello, i have a problem, my drivers side bank is running rich, i dont know what to check or where to go for expert help here in so cal, totally stk 2000, any help would be greatly appreciated

 

Your O2 sensors may be going bad.

Generally they both go bad around the same time.

If this is a lightning, and the innercooler leaked, that fluid will neutralize the catalytic convertor and foul out the O2's. (been there)

You might want to check the spark plugs, coil packs, and the injectors. (I clean my injectors periodically)

ALso, if you added Exhaust Mods (headers, Hi-flow cats) that makes the truck run richer.

 

thanks for your help

 

How do you know your one side is rich? Check your fuel pressure as well.