Instruct: Classify a given review into positive or negative sentiment.
Query: Good replacement part

I have been using this in my car (a 2002 Saturn SL2) for a year now, and have had no further check engine light warnings due to the O2 sensor.Home mechanics be warned though: it can be tricky to do the replacement yourself. I tried removing it manually with a wrench, then repeatedly tried using liquid wrench and tapping the sensor to loosen over the course of several days, to no avail. Finally I took it to my local repair shop, where a mechanic was willing to do the replacement for a low price. He had to use a torch to heat up the manifold to get it loose enough to remove the old sensor.Even after paying for the sensor, an hours labour and the engine code reader, it was significantly cheaper than paying a repair shop to diagnose and replace the O2 sensor.