As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOI - OIL SMELL IN CABIN ON DESCENT. AIRCRAFT LANDED IN BOI WITHOUT FURTHER PROBLEM. AIRCRAFT FERRIED TO PDX FOR REPAIR. NR 1 ENGINE REPLACED IAW MAINT MANUAL. ENGINE AND BLEED AIR OPS CHECKED GOOD ON GROUND RUN. AIRCRAFT RETURNED TO SERVICE. AWAITING ENGINE TEARDOWN FOR CAUSE.