MD80 CREW PULLS AND RESETS CIRCUIT BREAKER DURING TAXI TO CORRECT ENG PROB.

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IN 10000 HRS ON THE MD80 I HAVE NEVER SEEN THIS PROB BEFORE. AFTER ENG START AT 104 DEGS OUTSIDE AIR TEMP; WITH ABOUT 130 PAX ON BOARD; ATTEMPTED TO TAXI AWAY ON BOTH ENGS. WHEN THROTTLES ADVANCED; R ENG SPOOLED UP TO 1.10 EPR BUT L REMAINED AT 1.03 EPR. CONTINUED TO ADVANCE L THROTTLE TO VERT THROTTLE POS WHICH SHOULD HAVE GOTTEN ABOUT 1.4 - 1.6 EPR BUT EPR REMAINED AT 1.03 WITH NO MOVEMENT IN N1; N2; OR EGT. SHUT ENG DOWN AND RETURNED TO GATE. MAINT HAD US START L ENG AND THEN PULL CIRCUIT BREAKER S40; APCH IDLE CTL. WE WERE ASKED TO LET RPM RISE FOR ABOUT 5 SECONDS; RPM REACHED 65%; AND THEN CIRCUIT BREAKER PUSHED BACK IN; IDLE RPM RETURNED TO ABOUT 56%; NORMAL THROTTLE RESPONSE RETURNED TO L ENG. AFTER SHUTTING DOWN ENG; I ASKED MAINT WHAT THE PROB WAS AND THEY SAID THAT THIS WAS FAIRLY ROUTINE FOR A STUCK BLEED AND THIS WAS THE ROUTINE CORRECTIVE MAINT ACTION. IT SEEMED A BIT ODD TO ME AS MOST STUCK BLEEDS I'VE HAD ARE LOW IDLE RPM THAT CAN BE CORRECTED BY INCREASING RPM BY ADVANCING THE THROTTLE. IT WAS ALSO NOT THE PROB IN THE ABNORMALS THAT INDICATED THAT RPM WOULD INCREASE TO ABOUT 90-95% N2. PUSHED AWAY FROM GATE AGAIN; STARTING BOTH ENGS. AGAIN; IT APPEARED THAT L THROTTLE WAS NOT RESPONDING. WITHOUT DISCUSSING IT WITH FO WHO APPEARED TO BE BUSY WITH ACARS AND ACARS PRINTER I THOUGHT I'D SEE IF IT WAS THE SAME PROB BY PULLING AND RESETTING; THE APCH IDLE CTL CIRCUIT BREAKER. THE RESULT WAS THE SAME; NORMAL THROTTLE RESPONSE WAS RESTORED. I RESOLVED TO CONTACT MAINT ON LNDG IN RENO TO SEE IF THERE WAS ANY FOLLOW-UP ACTION THAT COULD BE TAKEN ON THE ORIGINAL DISCREPANCY THAT HAD RETURNED US TO THE GATE. IN DISCUSSING IT WITH TECHNICIAN; THEY SAID THEY WOULD NEED ANOTHER WRITE-UP. IT WAS ONLY THEN THAT IT FIRST STRUCK ME THAT I HAD PULLED A CIRCUIT BREAKER TO FIX THE PROB. I BRIEFLY CONSIDERED IF THERE WAS ANY WAY TO WRITE THE DISCREPANCY WITHOUT STATING THAT THE CIRCUIT BREAKER HAD BEEN ONCE AGAIN PULLED AND RESET.