You misunderstand his words just as the Jews did.
Your saying so does not mean it is the case. The context makes it pretty clear what Jesus is saying:
Joh 8:53 Are you greater than our father Abraham, who died? And the prophets died! Who do you make yourself out to be?"
Joh 8:54 Jesus answered, "If I glorify myself, my glory is nothing. It is my Father who glorifies me, of whom you say, 'He is our God.'
Joh 8:55But you have not known him. I know him. If I were to say that I do not know him, I would be a liar like you, but I do know him and I keep his word.
Joh 8:56Your father Abraham rejoiced that he would see my day. He saw it and was glad."
Joh 8:57 So the Jews said to him, "You are not yet fifty years old, and have you seen Abraham?"
Joh 8:58 Jesus said to them, "Truly, truly, I say to you, before Abraham was, I am."
Joh 8:59 So they picked up stones to throw at him, but Jesus hid himself and went out of the temple. (ESV)
In verse 58, Jesus makes a clear distinction between Abraham coming into being--"before Abraham
was"--and his timeless preexistence--"I am". Even if you want to deny that it "I am" here denoted timeless preexistence, although it does, there is absolutely no way around Jesus claiming to have existed before Abraham. And that was in direct response to the Jews' question regarding his having seen Abraham. The Jews
correctly recognized Jesus' claim to eternal preexistence and pick up stones to stone him, which was the penalty for blasphemy.