I remodeled my home. I ran all new outlets in bedroom(new addition). I installed an outlet for the outside patio and it Got covered over with sheeting before I could hook up the electrical outlet. The 4" box is there and the wire is ran to it and is live. But the carpenter covered it up with sheeting. I know the general location but I don't know the exact location. Is there a way to find location without ripping apart drywall? Please Reply.

Assuming the walls are studded at 16" centers, the outlets are most likely on one of them. A good quality inductance tester might find the hot wire. Since boxes are set at 12-16" off the floor, another possible way is to find a wall stud, drill a very small hole in the drywall, about 14" off the floor, on either side of the stud. Turn off the power before doing this. Insert a coat hanger bent to 90 degrees and with a tail of 4". Slowly rotate the hanger and if it hits something at about that height, you have probably found the box.

If you can disconnect the wire at the panel, both hot and neutral, you could use a signaal generator like used for tracing low voltage wire runs, such as telephone wire. Often called a "tic tracer" it would send a tone through the pair and you may be able to locate it, including where it ends with a tracer of this type.