My stud finder doesn’t seem to work…
Locate studs on an outdoor stucco wall with a magnet, your knuckle or a stud finder by checking along the same wall from indoors. A smooth, interior drywall surface can make locating studs easier. Mark the studs’ locations and measure the distance in between each one. Transfer these measurements to the outside wall remembering to factor in the thickness of the side walls.
They do have stud finders with deep scan capabilities. These stud finders can be found at Home Depot for around $50.
MultiScanner HD900 OneStep Multi-Function Wall Scanner $49.97
DeepScan mode doubles the scanning depth to 1-1/2 in. (38 mm)
When you knock on a stud it will have a different feel and sound than the hollow cavities.
Takes some practice but this is the original time tested stud finder.
Once you locate the first stud remember there should be continuity to how they framed the wall. Example: Studs 2’ on center etc. Hope this helps.
I suggest that you buy a stud detector from your local hardware store and locate the studs from indoors.
This magnetic stud finder works really well for me. I haven’t tried it through stucco yet though…