You don't really give enough information about your loss of power - however - it might be several things - clogged fuel filter - clogged fuel injectors - severely dirty/plugged air filter - spark advance is not working correctly. You might try taking it to a shop that can download and read the codes from the vehicle's OBD computer.
The 2008 Toyota Highlander is 6 ft. 3.2 in. (75.2 in.)1 one-touch power windows wide.
The 2001 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.
The 2010 Toyota Highlander is 6 ft. 3.2 in. (75.2 in.)1 one-touch power windows wide.
The 2009 Toyota Highlander is 6 ft. 3.2 in. (75.2 in.)1 one-touch power windows wide.
The 2004 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.
The 2003 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.
The 2005 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.
The 2013 Toyota Highlander is 6 ft. 3.2 in. (75.2 in.)1 one-touch power windows wide.
The 2007 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.
The 2012 Toyota Highlander is 6 ft. 3.2 in. (75.2 in.)1 one-touch power windows wide.
The 2006 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.
The 2002 Toyota Highlander is 5 ft. 11.9 in. (71.9 in.)1 one-touch power windows wide.