I have a 1987 190E 2.6. My brother-in-law was helping me replace the belt tensioner assembly. He's knows more than I do. After taking the old belt tensioner assembly and replacing it with the new one, the power steering stop working. Is it just a coincidence that the power steering pump failed or did he miss something when installing the new belt tensioner assembly. There's no leak that we notice, but opening the lid on the power steering pump shows no movement of the fluid, which my brother-in-law says that the power steering pump has failed and need to be replace. The power steering was working before replacing a part. Hope someone can give advice before purchasing a new power steering pump.