that all depends on what is leaking really.
Why would you ask a question where you only "believe" something? And how would you think you could get any kind of a good answer with nothing but a thought of something "might" that be. What were you thinking.
Under the right circumstances, it could cost you your life.
Could be a few hundred to $6k.
$0.99 up to about $500, if it even requires parts.
I have a 2002 Jeep Grand Cherokee Limited Edition, I believe it has a gas leak. How much would you say it would cost to be repaired?