Do you have a basic set of tools, wrenches and sockets? In the diagram below, looks like a nut on the backside of tensioner, that you take loose. If the alternator is in the way, remove it. Take negative battery cable loose, if you remove alternator.

Answered by JDL (expert)
14,416 answers provided

It can be done from the top if you reach behind the alternator. You'll need two different 15 mm wrenches because one won't turn the nut quite far enough to get the next bite.

caradiodoc

Answered by caradiodoc (expert)
17,303 answers provided