In its explicit theory of governance, the CCP acknowledges China is not "communist" yet. In the 70's, they decided they needed to grow as an economy before they could achieve communism (referring to Marx's stages of history where the economic development under capitalism paves the way for communism). This is sometimes called Dengism or "Socialism with Chinese Characteristics." So, they opened the economy up and that's where we are now: one of the world's largest, most productive capitalist economies.
The CCP remains a "communist" party because its ultimate stated goal is communism. But they seem quite a ways off from that, whatever that even means.