When your prayer life is lacking passion or the line of communication between you and God has become as erratic as cell coverage with AT&T.  These verses might help.

Isaiah 38:1-6  In those days Hezekiah became ill and was at the point of death. The prophet Isaiah son of Amoz went to him and said, “This is what the LORD says: Put your house in order, because you are going to die; you will not recover.”

Not the kind of news you want to hear.  Look how he handled it…

² Hezekiah turned his face to the wall and prayed to the LORD, ³ “Remember, O LORD, how I have walked before you faithfully and with wholehearted devotion and have done what is good in your eyes.” And Hezekiah wept bitterly.

Looked a little late for a prayer like that.  Maybe not.

⁴ Then the word of the LORD came to Isaiah: ⁵ “Go and tell Hezekiah, ‘This is what the LORD, the God of your father David, says: I have heard your prayer and seen your tears; I will add fifteen years to your life. ⁶ And I will deliver you and this city from the hand of the king of Assyria. I will defend this city.

Not a bad response.  Don’t be afraid to pray huge prayers.  The results could be life-changing.