Tip & How-To about Toyota Highlander
I agree with the previous answer that this a very time consuming job.
It took me 2+ hours. I would correct a couple of statements in his
answer. He refers to reaching around and behind an exhaust manifold
while changing the plugs, but actually if you are working from above the
engine (not below) you will be reaching around and behind the intake
manifold (not exhaust) during this process.
As he said, the front 3 are very easy - just remove the plastic cover plate and the coils are visible - remove one short bolt, pull the coil off, and using a long extension and a spark plug socket with a rubber insert you can remove the plugs and replace with new ones.
The back 3 are very, very difficult. I did look from underneath the car and I don't see any way to get to them even if the exhaust manifold was removed. I do believe the best way is from the top. As the previous answer related room to maneuver wrenches and your hands / fingers is very limited. I did remove a couple of minor brackets and hoses and the cruise control wire to get a little more room. Of course, as with the front, you have to remove each individual coil. Also - I believe two tools are critical. First - a small size "stubby" ratchet with a flexible head. You CAN use this type of small flexible ratchet to do the removal and install instead of all finger movement. Second - you need a number of small extensions.... in the 1" - 4" range... why??? because the rear plugs are also "deep" but there is no room to feed a single long extension down between the firewall and the engine head. So - you have to feed the spark plug socket and one short extension, and then feed in another one, and then a 3rd one if necessary until you get enough length to connect the socket to the plug, and the top extension to the ratchet. To remove the extensions - work in reverse.. pull the "assembly" out a little, remove one short extension, pull out further, remove another, etc until you get to the spark plug socket. On the 3 rear plugs - for two of the plugs you work from "your right" side of the intake manifold, or from the driver's side. For the final plug, on the passenger side, work from your left side of the intake manifold. On both sides remove minor hoses or brackets to get a little more room - just be sure to hook them back up.
Posted by Mark Brown on
Jul 09, 2016 | Jaguar Cars & Trucks
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