Nissan Xterra was created in 2000.
Your knock sensor is located undernesth the air intake manifold on top of the engine block. This goes for 2000-2004 xterra V6 3.3L models. Hope this helps.
The ground clearance of the 2011 Nissan Xterra is 0 ft. 8.1 in. (8.1 in.).
The ground clearance of the 2005 Nissan Xterra is 0 ft. 8.3 in. (8.3 in.).
The ground clearance of the 2010 Nissan Xterra is 0 ft. 8.1 in. (8.1 in.).
The ground clearance of the 2007 Nissan Xterra is 0 ft. 8.3 in. (8.3 in.).
The ground clearance of the 2006 Nissan Xterra is 0 ft. 8.3 in. (8.3 in.).
The ground clearance of the 2008 Nissan Xterra is 0 ft. 8.3 in. (8.3 in.).
The ground clearance of the 2013 Nissan Xterra is 0 ft. 8.2 in. (8.2 in.).
The ground clearance of the 2003 Nissan Xterra is 0 ft. 9.4 in. (9.4 in.).
The ground clearance of the 2014 Nissan Xterra is 0 ft. 8.2 in. (8.2 in.).
The ground clearance of the 2004 Nissan Xterra is 0 ft. 9.4 in. (9.4 in.).