Interesting, so MB improved the glow plug system on the later cars and got rid of that stupid strip fuse. I'm not sure how to test the system on that car then, again I'd refer to the FSM for testing procedures.


As to the tensioner, the aluminum rocker has a bearing in there. Make sure that ir moves freely without the shock and spring on it. Also make sure the pully spins freely. There is a diagram in the manual in your glove box that shows you how to route the belt, double check that. If all else fails replace the spring they are cheap, see where that gets you.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200