On the starter if 1 pos cable or midway if you have 2 pos cables & is remote mounted between.
The starter solenoid? Attached to the starter. Round thing, wires, etc.
The starter solenoid is mounted directly on the starter.
The starter solenoid is attached to the starter.
on the right side of the pickup follow the positive cable.
above the oil filter,to the left.
In the transmission.
Your starter solenoid is the ropund part attached to the top of your starter it has the little wire to trigger the starter drive to engage the flexplate and a big battery wire to spin it hope this answers you question
Your starter solenoid is sticking. Replace the starter solenoid and you should be good to go.
inside starter
The starter relay can be found underneath the hood on a 1991 Nissan pickup. The starter relay is beside the battery on the passenger side.
Need to know what size engine you have in order to answer your starter problem. 1993 Nissan pickup with v-6
inside starter.