the unstable rpm can be caused by a faulty O2 sensor. Also you will want to have your eacv cleaned out. Its located on the right side of the intake manifold if i am not mistaken. It has 2 hoses that run coolant towards it. It also has a green electrical connection clip that is connected to it. It is held in by 2 bolts. Try taking that out and cleaning it, sometimes that helps. Also check if your ecu is flashing any codes.