I replaced the entire AC system two years ago, and it has run great. However, a week ago I had to replaced the (original) radiator, and immediately afterwards I began hearing a new and very loud jackhammer-type noise, but only when the vehicle was in low RPMs. After several times hearing it, I pulled over but couldn't see anything. I pressed the accelerator, trying to emulate gear progression while in park, when "snap" something broke. It was the AC belt, snapped in half, not worn or otherwise damaged. After replacing the belt, the noise remained, but only occurring between 1.5-2.0 RPMs. I soon determined the AC tensioner would vibrate very violently, causing the jackhammer noise. I replaced it (twice, with two different brands), but the noise still crops up. The noise ONLY occurs when the AC is on. I don't want to automatically just replace the compressor, but does anyone have any ideas for why I'm having this noise? Could my new belt be too loose??
