Narrative:

For the fourth time in less than 30 days; I once again find myself compelled to report the company maintenance's mishandling of serious aircraft malfunctions; and their attempt to minimize and dismiss the issues without accepting the responsibility to troubleshoot and properly repair the problem. The end result in this instance was the aircraft experiencing multiple; related significant engine problems on takeoff from ZZZZ. On takeoff roll; the left engine did not reach the prescribed to (take-off) N1 setting and at rotation; it experienced an egt (exhaust gas temperature) overtemp; followed by a significant throttle split compared to the right engine for the remainder of the flight. However; of greatest concern to me is the time leading up to these event; beginning for me three days and several flights earlier. As my first officer and I assumed the aircraft at ZZZZ1; the off-going first officer expressed to me his frustration and concern with the left engine. I discussed it with the off-going captain but he did not want to write it up. Enroute back to ZZZZ3; we experienced the same problems they expressed; slow to accelerate to commanded thrust and a throttle split. We also noticed the command sector on the left N1 gauge remained in view for the entire flight. We elected to write these discrepancies up in ZZZZ3.we re-assumed the aircraft two days later. I immediately investigated how maintenance cleared the write-up and if the intermediary crew had written it up again. Maintenance had done nothing more than a 'maintenance check' and found no discrepancies and the crew had made no write-ups of any kind. The aircraft and engine were far from fixed however; and we experienced the exact same problems on the fight and therefore we again wrote them up. Contract maintenance at ZZZZ4 was woefully unprepared to do any work on the engine and the decision was made by the company's maintenance control; over my objection; to defer the left engine eec (electronic engine control); which required us to turn off both eecs. After 'timing out' in ZZZZ; we came back out the next morning; when the mishap occurred and were asked by the service provider and advised by flight control to perform a maximum weight; maximum thrust takeoff on the longest runway. I asked if this was a good idea due to the eecs being disabled and was simply told 'we can do it'. We did do it; with the resulting thrust and overtemp conditions occurring as above. I decided not to abort the takeoff as the N1 was within 2% of the desired and we were already traveling well in excess of 100 KIAS; and I believed it safer to continue than to attempt a high speed; high altitude; heavy weight abort. We closely monitored the engine on the way back to ZZZZ3 and with the exception of the large throttle split; no other problems were observed or encountered. After landing at ZZZZ3; I both wrote up all three occurrences and called maintenance control; who were not concerned and in fact told me the egt overtemp wasn't a concern. In fact; the aircraft required a new mec (main engine control) and sat broken for the next five days.

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Original NASA ASRS Text

Title: B767 Captain reported that one of the engines was seriously under performing due to maintenance issues.

Narrative: For the fourth time in less than 30 days; I once again find myself compelled to report the company maintenance's mishandling of serious aircraft malfunctions; and their attempt to minimize and dismiss the issues without accepting the responsibility to troubleshoot and properly repair the problem. The end result in this instance was the aircraft experiencing multiple; related significant engine problems on takeoff from ZZZZ. On takeoff roll; the left engine did not reach the prescribed TO (Take-off) N1 setting and at rotation; it experienced an EGT (Exhaust Gas Temperature) overtemp; followed by a significant throttle split compared to the right engine for the remainder of the flight. However; of greatest concern to me is the time leading up to these event; beginning for me three days and several flights earlier. As my First Officer and I assumed the aircraft at ZZZZ1; the off-going First Officer expressed to me his frustration and concern with the left engine. I discussed it with the off-going Captain but he did not want to write it up. Enroute back to ZZZZ3; we experienced the same problems they expressed; slow to accelerate to commanded thrust and a throttle split. We also noticed the Command Sector on the left N1 gauge remained in view for the entire flight. We elected to write these discrepancies up in ZZZZ3.We re-assumed the aircraft two days later. I immediately investigated how maintenance cleared the write-up and if the intermediary crew had written it up again. Maintenance had done nothing more than a 'maintenance check' and found no discrepancies and the crew had made no write-ups of any kind. The aircraft and engine were far from fixed however; and we experienced the exact same problems on the fight and therefore we again wrote them up. Contract maintenance at ZZZZ4 was woefully unprepared to do any work on the engine and the decision was made by the company's Maintenance Control; over my objection; to defer the left engine EEC (Electronic Engine Control); which required us to turn off both EECs. After 'timing out' in ZZZZ; we came back out the next morning; when the mishap occurred and were asked by the service provider and advised by Flight Control to perform a maximum weight; maximum thrust takeoff on the longest runway. I asked if this was a good idea due to the EECs being disabled and was simply told 'we can do it'. We did do it; with the resulting thrust and overtemp conditions occurring as above. I decided not to abort the takeoff as the N1 was within 2% of the desired and we were already traveling well in excess of 100 KIAS; and I believed it safer to continue than to attempt a high speed; high altitude; heavy weight abort. We closely monitored the engine on the way back to ZZZZ3 and with the exception of the large throttle split; no other problems were observed or encountered. After landing at ZZZZ3; I both wrote up all three occurrences and called Maintenance Control; who were not concerned and in fact told me the EGT overtemp wasn't a concern. In fact; the aircraft required a new MEC (Main Engine Control) and sat broken for the next five days.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.