I have an '87 190e 16v. How can I tell if the chain tensioner has been updated? I don't get any rattling on startups, even when it's cold. And it has been cold lately.

There are 3 different tensioners that will fit this engine. Only the latest version will keep the chain tight. They look simular. The only way to identify the RIGHT version is to look at the end of the cap nut, it has a place to install an allen bit.