Did you clean the IAC motor out.They get dirty and make them idle rough,up and down.Should be a hole in the T/B on either side of the butterfly.You can spray some carb cleaner in it and let it soak and spray it and let it soak and spray it and let it soak until it comes out clean on the back side of the butterfly.Run some through the PCV hose too,they suck up a bunch of crud.