Where is the low pressure port on 1998 Nissan quest ac?

On a 1998 Nissan Quest, the low-pressure port for the air conditioning system is typically located on the larger diameter aluminum line that runs between the compressor and the evaporator. It is usually situated near the firewall, on the passenger side of the engine compartment. The port is designed for charging the AC system and is often covered with a cap that may be labeled. Always ensure the system is off and the vehicle is in a safe state before attempting any service.