There is a DIY for the CCV valve replacement. You can pull the 2 diaphragm valves & look for cracks in the rubber. These cost around 20.00 a piece. I would also check the 2 hoses coming from the front of the valve covers, that run to the front of the intake. These crack often from dry rotting, allowing a vacuum leak.
Check these 2 items & get back with us.