New oil pressure sender faulty?

Yup, junk in the box. Way more now than 20 years ago.
you can say that again , have a buddy with a parts store , it is just insane the amount of defective new parts returned , then there is the failure rate if the parts do work for a while . Standard , do they still carry 2 lines of products ? junk and worse junk . that's what we get for going the cheapest route