How long do you cook a 4 lb pork tenderloin in crock pot?

A 4-pound pork tenderloin will typically take 6-8 hours to cook on low in a crock pot, or 3-4 hours on high. To ensure the pork tenderloin is cooked thoroughly, use a meat thermometer to check the internal temperature. The pork tenderloin is done when the internal temperature reaches 145 degrees Fahrenheit. Let the pork tenderloin rest for 10-15 minutes before slicing and serving.