I recently purchased a greddy catch can and installed it. valve cover to catch can to intake manifold. so when I was installing it, I noticed that obviously the pvc valve and intake manifold port has a smaller port compared to the greddys ports. so I got adapters to fit the greddys bigger ports. after install, I drove it around and at a stop I noticed that the idle drops really low. there were a few instances that the car spuddered like it leaned out. this mostly happened at low rpm. so I disconnected the battery to reset the car. connected the battery back and drove around and it just kept dying when stopping. so now I connected the hose from the pvc to the intake manifold back on and its fine again. WTF is going on? how do I stop the idle drop? should I use smaller hoses? are my current hoses too big? I imagine is like a big vaccum leak on the intake manifold because the hoses are kinda big. any one else have this problem?

its a 02 with 144k. the greddy is the NON vented one.