Run the following command at your node.js command prompt where "<git path>" is the path to your git bin folder:
set PATH=%PATH%;<git path>;
So, like this:
set PATH=%PATH%;C:\Program Files\Git\bin;
Or this: (Notice the (x86) )
set PATH=%PATH%;C:\Program Files (x86)\Git\bin;
This will add git to your path variables. Be sure you type it correctly or you could possibly delete your path vars which would be bad.