Originally Posted by afpj

I, along with a handful of people on the Toyota nation highlander form, removed The carbon mesh filter immediately downstream of the paper engine air filter. To me, this is a point of potential restriction and by removing it I think I feel better throttle response and better shifting. No change in sound however. Of course YMMV. It was an experiment to try since I had time on my hands that particular day and I am way out of warranty.