Last year I added refrigerant to my a/c to cool down the temp some. When it got warm this year it needed more, so I figured there was a slow leak somewhere. I added most of a tall can of the kind with oil. When I stopped and unhooked the hose to put the cap back on the compressor started going in and out constantly. Was getting very cold but would keep cutting off and on. Had a guy look at it and he said the problem was me adding the kind with oil. Somehow he got some of the oil out and added regular to it. Worked great for a few days. Now it is back to doing the same thing. Help.......Please