An apparatus which prevents objectionable increases in air pressure in a passenger compartment of a vehicle upon closing of a door (38, 38a, 38b) of the vehicle, said apparatus comprising: a vent valve (32, 32a) which is movable between a closed condition blocking air flow through a vent opening (48, 48a, 48b) and an open condition enabling air to flow through the vent opening (48, 48a, 48b); a door position sensor assembly (62, 62a, 62b) which is operable from a first condition to a second condition in response to movement of the door (38, 38a, 38b) of the vehicle from a closed position to an open position, said door position sensor assembly (62, 62a, 62b) being operable from the second condition to the first condition in response to movement of the door (38, 38a, 38b) of the vehicle from the open position to the closed position; and an actuator assembly (34, 34a, 34b) which is connected with said door position sensor assembly (62, 62a, 62b) and said vent valve (32, 32a), said actuator assembly (34, 34a, 34b) being operable to operate said vent valve (32, 32a) from the closed condition to the open condition upon operation of said door position sensor assembly (62, 62a, 62b) from the first condition to the second condition, said actuator assembly (34, 34a, 34b) being operable to release said vent valve (32, 32a) for movement from the open condition to the closed condition upon operation of said door position sensor assembly (62, 62a, 62b) from the second condition to the first condition, wherein said actuator assembly (34, 34a, 34b) includes a force transmitting member (64, 64a, 166) connected with said vent valve (32, 32a), said force transmitting member (64, 64a, 166) moving from a first position to a second position upon operation of said door position sensor assembly (62, 62a, 62b) from the first condition to the second condition, said force transmitting member (64, 64a, 166) moving said vent valve (32, 32a) from the closed condition to the open condition when said force transmitting member (64, 64a, 166) moves from the first position to the second position, wherein a first spring (78, 78a) or a solenoid moves said force transmitting member (64, 64a, 166) from the first position to the second position to move said vent valve (32, 32a) from the closed condition to the open condition upon operation of said door position sensor assembly (62, 62a, 62b) from the first condition to the second condition, wherein a second spring (112, 112c, 186, 210) or a magnet urges said vent valve toward the closed condition, and wherein a first end section (100, 100a, 100b) of said force transmitting member (64, 64a, 166) extends into a slot (104, 104a, 104b) in said vent valve (32, 32a) to provide a slide connection (94, 94a, 94b) with said vent valve (32, 32a). a vent valve (32, 32a) which is movable between a closed condition blocking air flow through a vent opening (48, 48a, 48b) and an open condition enabling air to flow through the vent opening (48, 48a, 48b); a door position sensor assembly (62, 62a, 62b) which is operable from a first condition to a second condition in response to movement of the door (38, 38a, 38b) of the vehicle from a closed position to an open position, said door position sensor assembly (62, 62a, 62b) being operable from the second condition to the first condition in response to movement of the door (38, 38a, 38b) of the vehicle from the open position to the closed position; and an actuator assembly (34, 34a, 34b) which is connected with said door position sensor assembly (62, 62a, 62b) and said vent valve (32, 32a), said actuator assembly (34, 34a, 34b) being operable to operate said vent valve (32, 32a) from the closed condition to the open condition upon operation of said door position sensor assembly (62, 62a, 62b) from the first condition to the second condition, said actuator assembly (34, 34a, 34b) being operable to release said vent valve (32, 32a) for movement from the open condition to the closed condition upon operation of said door position sensor assembly (62, 62a, 62b) from the second condition to the first condition, wherein said actuator assembly (34, 34a, 34b) includes a force transmitting member (64, 64a, 166) connected with said vent valve (32, 32a), said force transmitting member (64, 64a, 166) moving from a first position to a second position upon operation of said door position sensor assembly (62, 62a, 62b) from the first condition to the second condition, said force transmitting member (64, 64a, 166) moving said vent valve (32, 32a) from the closed condition to the open condition when said force transmitting member (64, 64a, 166) moves from the first position to the second position, wherein a first spring (78, 78a) or a solenoid moves said force transmitting member (64, 64a, 166) from the first position to the second position to move said vent valve (32, 32a) from the closed condition to the open condition upon operation of said door position sensor assembly (62, 62a, 62b) from the first condition to the second condition, wherein a second spring (112, 112c, 186, 210) or a magnet urges said vent valve toward the closed condition, and wherein a first end section (100, 100a, 100b) of said force transmitting member (64, 64a, 166) extends into a slot (104, 104a, 104b) in said vent valve (32, 32a) to provide a slide connection (94, 94a, 94b) with said vent valve (32, 32a).