Jesus Christ is the one making intercession for us. It is He that is currently seated at God's right hand, not Mary. She was a wonderful woman! She was the one that believed God when he spoke to her about bearing a child. She said let it be according to your will. But that is all she did. Jesus Christ is the savior of mankind, not Mary. We are instructed to pray to God, in the name of Jesus Christ. Not to pray to Mary.
Read your Bible!!