As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE CLT TO TOL, WHEN THE NR 4 TURBO COMPRESSOR WAS TURNED ON, A LOUD HOWL WAS HEARD AND RPM STARTED TO FLUCTUATE. THE T/C RPM THEN WENT TO ZERO VERY RAPIDLY, THE T/C WAS SECURED. AN ACRID SMELL WAS SENSED IN THE COCKPIT AS THE T/C RPM DROPPED TO ZERO. MAINTENANCE DEFERRED THE TURBO COMPRESSOR IN ACCORDANCE WITH THE DC-8 MEL AND RETURNED THE AIRCRAFT TO SERVICE.