What was found
AIRCRAFT WAS GROUNDED: IMMEDIATELY AFTER TAKE OFF COCKPIT AND CABIN HAD STRONG, OVEN, BURNING SMELL. FLIGHT ATTENDANTS CONFIRMED SMELL WITH NO SMOKE OR HAZE IN CABIN. SMELL DISSIPATED COMPLETELY IN 1 TO 2 MINUTES, OVENS WERE OFF AND APU WAS OFF AND INOPERABLE. MAINTENANCE ACCOMPLISHED MCM CARD 05-96-70 TYPE 4, FOUND RIGHT HAND AIRCRAFT PRESSURE REGULATOR, SHUTOFF, VALVE BAD, AND REPLACED VALVE PER MM 21-31-01. PERFORMED SATISFACTORY OPERATIONAL CHECKS, NO ODOR NOTED.