It's not so much the chain, as it is the rails. With age and heat and whatever other things in their surroundings they are assaulted by, they simply get brittle. One day, the chain slaps up against it a little too hard (usually at start up - there are no other symptoms, unless you can identify the sound of chainslap).

Most folks, when they replace the guides, replace the chain at the same time - might as well, since you are already in there. In my case, on my 420, it was discovered that I had bad lifters and that the cam was on it's last leg. Rumor has it, that those 2 items are not all that unheard of.

Personally, although I liked the ride and most other things about the 126, I do prefer my 124 (E420). Not only is it a good bit shorter, but it has less body roll, is shorter and lenght, has 74 more HP and gets 23-24mpg (vs. 17ish in the 126).

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D