ACR MLG ABORTED TKOF DUE TO UNEVEN POWER ON POWER APPLICATION AND UNWANTED ARTS; AUTOMATIC RESERVE THRUST; ACTIVATION WHEN POWER ADJUSTED.

Narrative

THE AUTO RESERVE THRUST SYS ACTIVATED DURING THE APPLICATION TO TKOF PWR. THE TKOF WAS DISCONTINUED. AFTER CLRING THE RWY; THE ENGS WERE RUN UP AND THEY CHK OUT OK. THE TKOF WAS MADE AND EVERYTHING WAS NORMAL. IN CRUISE; WHILE ADJUSTING PWR; IT WAS NOTICED THAT THE EPR GAUGES RESPONDED TO THE OPPOSITE ENGS. THE EPR GAUGES WERE WIRED BACKWARDS. THE EPR GAUGE REVERSAL WAS NOT NOTICED DURING THE ENG RUN UP CHK BECAUSE BOTH ENGS WERE RUN UP SIMULTANEOUSLY. LOOKING FOR A SPREAD IN ENG GAUGE READING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: F/O WAS MAKING THE TKOF. WHEN HE APPLIED THE PWR THE L ENG WAS A LITTLE HIGH SO CAPT ADJUSTED THE L THROTTLE BACK ONLY TO HAVE THE L ENG INCREASE THRUST. NOT REALIZING WHAT THE PROB WAS THE TKOF WAS ABORTED RETURNED TO RUNUP PAD AND RAN UP BOTH ENGS. THIS TIME THEY PERFORMED NORMAL SO TRIP DEPARTED. ENRTE CAPT WONDERED IF MAYBE A FUEL CTLR PROB SO TO GET INFO FOR MAINT HE PULLED THROTTLES BACK INDIVIDUALLY AND DISCOVERED THE ENG PRESSURE GAUGES REVERSED. THIS WAS WHEN THE CREW REALIZED THAT ON THE ORIGINAL TKOF RUN THE ENGS PERFORMED PROPERLY. THIS MODEL HAS A SYS THAT SENSES ENG FAILURE AND WHEN N1 RPM OF ONE ENG IS 30% BELOW THE OTHER ENG IT SHIFTS THE FUEL CTL TO GIVE THE GOOD ENG AN EXTRA 850 LB OF THRUST. SO WHEN THROTTLE ADJUSTED ON FIRST TKOF RUN WITH REVERSED EPR GAUGES; CAPT ACTUALLY REDUCED LOW ENG TO CAUSE 30% SPREAD AND KICK IN THE AUTO RESERVE THRUST. LATER IT WAS ASCERTAINED THE ACFT HAD HAD MAINT 2 NIGHTS BEFORE AND HAD FLOWN ALL THE PREVIOUS DAY WITH THE EPR GAUGES REVERSED BY THREE DIFFERENT CREWS AND SINCE ENGS HAD ALWAYS BEEN EVEN THE ERROR BY MAINT WAS NOT DISCOVERED. RPTR HAD NOT FOLLOWED UP AFTER THE INCIDENT BUT IS FAIRLY CERTAIN THAT THE CANNON PLUGS HAD BEEN REVERSED AT THE GAUGES BEHIND THE INSTRUMENT PANEL SINCE THIS IS THE ONE PLACE WHERE THE ENG WIRING IS CLOSE TOGETHER.