93 mercedes 190e belt tensioner
Has there been a known problem with this part going out? My mom took it in to get the
belt replaced and after they put the new one on they came back and said that the belt
tensioner was squeaking and appeared to be loose and told here that it needs to be
replaced. They said that it was going to be 400 for the part and 3 hours of labor. When
she told me this I thought they were blowing smoke in her face cause I found the part at
auto zone for 188.99. Is it there fault it's supposedly not working right?