South Park Episode 302 - "Spontaneous Combustion"
Kenny spontaneously combusts.
The mayor asks Randy Marsh to find a solution. The boys try to help Kyle's dad to get an erection. One way they think they can help is by performing the Stations of the Cross at church crucifying Cartman and waiting three days for his res-erection. Randy Marsh figures out the reason everyone is combusting is because they are withholding their farts.