AN MD80 IN LEVELOFF AT FL330 DIVERTED DUE TO THE L ENG SPOOLED DOWN TO 70% N1 WITH COMPRESSOR STALLS CAUSED BY INOP BOOST PUMP PLACARDING ERROR.

Narrative

AFTER REVIEWING THE LOGBOOK OF TAIL XYZ; I NOTED THAT THE L AFT BOOST PUMP WAS WRITTEN UP FOR POPPING THE CB ON OCT/MON/00. I THEN NOTED THAT A BOOST PUMP WAS PLACARDED INOP AND LOGBOOK SIGNED OFF PER THE MEL. WE DEPARTED ABQ WITH THE PLACARDED SWITCH IN THE 'OFF' POS. WHILE CLBING THROUGH FL300 THE L ENG INLET FUEL PRESSURE LOW ANNUNCIATOR BEGAN TO FLICKER. I BEGAN RUNNING THE CHKLIST WHILE THE ANNUNCIATOR WAS NOW ON STEADY. AFTER LEVELING OFF AT FL330; THE L ENG ROLLED BACK TO APPROX 70% N1 AND BEGAN TO COMPRESSOR STALL. CAPT DISCONNECTED THE AUTOTHROTTLES AND THE AUTOPLT AND MAINTAINED ACFT CTL. WHILE I RAN THE CHKLIST AND AFTER TURNING THE XFEED ON AND THE ANNUNCIATOR EXTINGUISHING; WE ASSUMED DUEL BOOST PUMP FAILURE. SINCE THE ENG APPEARED NOT TO BE SUCTION FEEDING; WE ELECTED TO LEAVE THE FUEL XFEED ON TO ENSURE ENG OP UNTIL LNDG. DUE TO POSSIBLE ENG FAILURE AND IMPENDING FUEL IMBALANCE; WE COORDINATED WITH ATC AND DIVERTED TO ABQ WITH NO FURTHER INTERRUPTION OF ENG OP. AFTER DISCUSSIONS WITH MAINT; IT WAS DISCOVERED THAT THE FORWARD BOOST PUMP WAS INCORRECTLY PLACARDED BY ZZZ MAINT ON OCT/MON/00; INSTEAD OF THE AFT BOOST PUMP.