Narrative:

On initial climb out everything was normal; all engine gauges in the green. Upon reaching 5;000 feet during climb my left engine gauges started to drop to the yellow arc while the right gauges started to increase slightly. While this was starting my HSI stopped working correctly and the left alternator light came on; as I ran the checklist and asked departure to stay with them. The light went out; I did not change anything and it came back on and then off about 5 times after the initial light up. I called dispatch on the radio but by the time maintenance was on the radio; the gauges were getting worse. So I told them and ATC I was needing to return. As I was flying back the left engine had a random surge to it. On final my left engine was needing a lot more throttle than the right to stay on path. I did not declare an emergency with ATC; but considering my situation I treated it as one in the airplane and was able to taxi it back to the hangar.

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Original NASA ASRS Text

Title: The pilot of a PA31 experienced issues with the left engine during climb and elected to return to the departure airport.

Narrative: On initial climb out everything was normal; all engine gauges in the green. Upon reaching 5;000 feet during climb my left engine gauges started to drop to the yellow arc while the right gauges started to increase slightly. While this was starting my HSI stopped working correctly and the left alternator light came on; as I ran the checklist and asked departure to stay with them. The light went out; I did not change anything and it came back on and then off about 5 times after the initial light up. I called dispatch on the radio but by the time maintenance was on the radio; the gauges were getting worse. So I told them and ATC I was needing to return. As I was flying back the left engine had a random surge to it. On final my left engine was needing a lot more throttle than the right to stay on path. I did not declare an emergency with ATC; but considering my situation I treated it as one in the airplane and was able to taxi it back to the hangar.

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.