Replaced air conditioning compressor. Seemed to be working great in the shop. Drove about 150 miles and it feels like the rebuilt compressor is locking up. When I turn AC on while moving, something makes a noise and there is hesitation in the engine. Stops when I turn off the AC. Replaced the serpentine belt tensioner and checked the belt before a rebuilt compressor was installed and it wasn't the tensioner. Could it be the rebuilt compressor? It cost $250.00. 2 hours labor @ $75 per hour. Insight please. Actually the noise was there before the Compressor replacement, but it was slight and only happened when I accelerated from a dead stop. Dye test indicated a leaking compressor valve so I thought it was the compressor seizing up.