What is this doctor's tool that mechanics often use to diagnose engine problems?

Your doctor listens to your ticker with a stethoscope, and your mechanic does the same thing for the heart of your car's engine. While mechanics started off using the medical model, modern versions are wireless and allow the technician to diagnose problems while driving the vehicle.

Asked by Don Ayres · Last updated 5 years ago · 530.8K views · SOURCE