As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
N985DS WAS SHOOTING APPROACHES INTO KWRI WHEN A LOUD NOISE WAS HEARD AND EXHAUST WAS SMELLED IN THE CABIN. AN IN-FLIGHT EMERGENCY WAS DECLARED AND THE AIRCRAFT LANDED. UPON EVALUATION BY MAINTENANCE IT WAS DISCOVERED THE #3 EXHAUST RISER HAD SEVERED ADJACENT TO THE "Y" WELD AND WAS LAYING INSIDE THE COWLING.