My chevy 5.3 idles low

Clean the throttle valve and the air bypass idle speed control valve, they get full of sludge and restrict air flow, this causes a low idle at times and the engine will stall, clean them by spraying carb spray into the throttle valve while the eng is running, have someone hold the idle high or it will stall, after using at least 1/2 can shut down and disconnect the battery for 5 minutes, this clears the memory and allows the computer to relearn idle strategy, the computer willl take a few days to relearn the idle, maybe 30 miles of mixed driving.