It should be in the owner's manual or if you don't have that the answer is 1.1 mm.
Your gap should be (Gap 0.044inch) for DOHC 2.5l Altima
0.044 is your spark plug gap.
0.44
.044
Most all auto spark plugs that are sold today are already properly gapped for the auto they are going into. If you visit your local auto parts store, they can look up the plugs for your Nissan Altima and you won't have to gap the plugs yourself.
0.44 in.
It is 1.0 mm to 1.1 mm or 0.039" to 0.043" You can check in the manual for Nissan 1997 Altima
0.040 inch
The correct spark plug gap is .044
The gap should be 0.043 inch.
.44
0.44