DURING FUEL XFEED IN AN MD80; AN INLET FUEL LOW PRESSURE LIGHT CAME ON ALONG WITH A THUMP SIMILAR TO A COMPRESSOR STALL. A FAULTY XFEED VALVE WAS DETERMINED TO BE THE CAUSE.

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JUST PRIOR TO DSCNT; CAPT REQUESTED THAT I BAL MAIN TANK 500 LB IMBAL (CTR EMPTY; 10000 LBS TOTAL REMAINING). I SET UP FOR THE XFEED; AND AS I TURNED OFF THE LOW SIDE PUMPS (R); THERE WAS AN AUDIBLE THUMP; A BRIEF SHUDDER; AND THE 'R INLET FUEL LOW PRESSURE' LIGHT ILLUMINATED AND WENT OUT. THE PUMPS WERE IMMEDIATELY RESTORED; AND THE ENGS CONTINUED NORMALLY THROUGHOUT; ALTHOUGH THE FLT ATTENDANT IN THE REAR CABIN CALLED TO INQUIRE ABOUT THE THUMP. WE THEN DECIDED TO REPEAT THE PROC USING THE OTHER SIDE; TO CHK ALL MAIN TANK PUMPS' OP. AS WE TURNED OFF THE L MAIN PUMPS; THE SAME OCCURRED AS ABOVE. WE IMMEDIATELY RESTORED NORMAL OP AND REFERRED TO THE ENG COMPRESSOR STALL BULLETIN AND 'INLET LOW PRESSURE' QRH. AS ALL WAS NOW NORMAL AND WE WERE EQUIDISTANT FROM ZZZ AND ZZZ1; WE DECIDED TO CONTINUE TO ZZZ1 AS CONDITIONS ALONG THAT RTE WERE CLR; ZZZ WAS CLOUDY. THE CAPT INSTRUCTED ME TO CONTACT MAINT CTL ON VHF #2 FOR ADVICE; BUT THE RANGE WAS SUCH THAT COMS WERE BROKEN AT BEST. APPARENTLY THEY THOUGHT WE HAD A FUEL TOTAL PROB AND REQUESTED VIA DISPATCH ACARS MESSAGE THAT WE LAND ASAP IN ZZZ. THIS WOULD HAVE MEANT A 180 DEG TURN AND MORE TRACK MI THAN CONTINUING TO ZZZ1; SO WE DECLARED AN EMER AS A PRECAUTION AND ROUTED DIRECTLY TO RWY 13R AT ZZZ1. DISPATCH WAS CONTACTED ON VHF #2 AND APPRISED OF THE TRUE SITUATION; AND CONCURRED WITH THE CAPT'S DECISION TO CONTINUE TO ZZZ1. ZZZ2 AND ZZZ3 WERE AVAILABLE AS ENRTE DIVERSIONS IF NECESSARY. THE ACFT PERFORMED NORMALLY THROUGHOUT; AND ALL PARAMETERS WERE NOTED FOR THE LOGBOOK ENTRY FOR LATER. THE ACFT WAS LANDED SAFELY AT ZZZ1 AND TAXIED TO THE GATE ACCOMPANIED BY CFR. IN SUMMARY; IT WOULD APPEAR THAT THE ACFT HAD SUFFERED FROM SOME KIND OF MOMENTARY FUEL FEED PROB WITH CROSSFEEDING TO EITHER ENG. I TOTALLY CONCUR WITH THE CAPT'S DECISION TO CONTINUE INTO VFR CONDITIONS AHEAD; RATHER THAN TURN BACK INTO THICK CLOUD TO ZZZ. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THEY WERE NOT SURE IF THE ENGS STALLED OR NOT AS THERE WERE NO ENG INDICATIONS THAT WOULD VERIFY A STALL. THE PROB WAS CAUSED BY A STICKY XFEED VALVE THAT WAS REPLACED. THE CREW DECLARED AN EMER AND LANDED UNEVENTFULLY AT THEIR DEST ARPT.