Toyota Highlander Service Manual: Ignition system (2AZ-FE)

Ignition

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On-vehicle inspection

NOTICE: In this section, the terms "cold" and "hot" refer to the temperature of the coils. "Cold"means approximately -10 C (14 F) to 50 C (122 F). "Hot" means approximately 50 C (122 F) to 100 C ...

More about Toyota Highlander:

Off-road driving
Your vehicle is not designed to be driven off-road. However, in the event that off-road driving cannot be avoided, please observe the following precautions to help avoid the areas prohibited to vehicles.  Drive your vehicle only in areas where off-road vehicles are permitted to trave ...