What series of events led the characters to resolve a problem, in chapter 4 of lightning theif

Chapter 4 of The Lightning Thief finds Percy in the car with his mother and his best friend, Grover, heading to what Percy believes is a summer camp and being chased by something that has both Grover and Percy’s mom incredibly scared.
There are two problems to examine in Chapter 4.  The first and more obvious is the fact that a mythological creature is chasing them down, wanting to kill Percy and probably everyone with him.  The second problem is that Percy is just now discovering that the mythical world he’d learned about in school is real. He is completely unprepared for the world he is about to be launched into.
How do they solve the problem of the Minotaur? The car goes into a ditch, possibly hit by lightning, and the three of them have to abandon it.  That’s when Percy realizes that the man after him is Not a Man.  Percy’s mom wants him to leave them and run to safety, but Percy refuses to leave them behind.  He gets her to help drag a nearly unconscious Grover out of the car. 
Percy learns from his mom that the creature has several weaknesses, much like a regular bull. Percy's mom gives him the plan: when the creature charges, wait until the last second then jump to the side. It works the first time, but now Percy is separated from the others.
The Minotaur charges again, this time at Percy’s mom. She tries the same trick as before, but the creature catches her in his massive hand. The shock and grief of seemingly watching his mother die right before his eyes gives Percy a rush of energy and strength.  He distracts the Minotaur from his friend on the ground by waving his red jacket and yelling, positioned in front of a massive pine tree. Instead of jumping to the side at the last minute, he jumps straight up and lands on the back of the creature’s neck while it brains itself on the tree.  During the ensuing struggle he manages to break off a horn, which gets him thrown off and bashed against a rock on the ground.  When the Minotaur charges again, Percy stabs it with its own horn and succeeds in killing it.  He watches as it turns to dust and blows away: more evidence that he’s in a whole new reality.
The problem of Percy’s lack of knowledge is far more central to the plot.  The events that led the supporting characters, Grover and his mom, to expose themselves to Percy actually happen in Chapter 3 when Percy is attacked and they make the decision to get Percy to camp.  By Chapter 4, Percy has discovered that his best friend is not human; he’s a satyr with goat legs. Grover admits that it was his job to “watch” Percy and that part of that job was to make sure Percy remained oblivious.  He inadvertently drops a comment that “You started to realize who you are,” which alerts Percy to the fact that he may be more than human.  Grover then further admits that Mrs. Dodds was real and that the old ladies at the fruit stand were actually the Fates.
Percy discovers that his mother knows all about the reality of mythological creatures and has been keeping this from him his whole life. His mom drops hints that the summer camp they are racing towards is not just an ordinary camp, but a place where he will be safe.  In the middle of the fight with the Minotaur, she reveals that she can’t go with them—she can’t cross the property line.  At the time, Percy doesn’t understand why that is.
All these hints and introductory “reveals” are not enough to make Percy aware of who he is and the nature of the world he belongs to, but Grover and Percy’s mom do provide a solid foundation to help prepare Percy for the revelations that will be coming in the subsequent chapters.