2010 Toyota Highlander Owners Manual - Page 456

4-3. Do-it-yourself maintenance CAUTION n Safety glasses Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in the eyes. NOTICE n If you remove the air cleaner filter Driving with the air cleaner filter removed may cause excessive engine wear due to dirt in the air. Also a backfire could cause a fire in the engine compartment. 4 Maintenance and care 431