The 1994 Honda Civic air conditioning low pressure port is located on top of the air conditioner compressor. The low pressure port will have a blue top.
The 2004 Civic low pressure air conditioning service port can be found on top of the air conditioner compressor. The low pressure port should be labeled as such.
The 2001 Honda Civic OBD 2 port is on lower right edge of dash; behind console trim
The 1998 Honda Civic OBD 2 port is under driver side dash next to kick panel
The 2003 Honda Civic OBD 2 port is behind center console
The 2006 Honda Civic OBD 2 port is under driver side dash next to center console
The 1997 Honda Civic OBD 2 port is on drivers side,connector faces down
The 2004 Honda Civic OBD 2 port is behind kick panel; above accelerator pedal
The 2001 Honda Civic OBD 2 port is on lower right edge of dash; behind console trim
The 1996 Honda Civic OBD 2 port is under dash on left side connector faces down
The port is on the cold ac pipe located toward the front of the engine on the manifold side. It is usually marked with a blue dust cap.
The 1996 Honda Civic OBD 2 port is on driver side,connector faces down
On Honda Civic 1997, the OBD-II port is located below the steering unit (roughly where your left knee hits the covered unit below your steering wheel.) To access the port, bend down and look underneath the steering column, where the covered fuse box is located too. I hope you can locate the port now.