Recommended Maintenance

Yep; the entire wiper assembly needs to be removed to get to them. A real PITA; luckily only needed to be done every 100K+ miles. Hopefully you don't loose an ignition coil back there; otherwise more fun!!!!
A friend of mine had a Sienna with an intermittent miss on #3. I told him I'd help him and to buy both sets of ignition coils and iridium plugs. When I arrived; he was whining about the cost; so I instructed him on how to get to those rear plugs while I stood there and drank beer. He realize why I had him buy both sets as he was removing the first rear ignition coil. When we were finished, we troubleshot the rear set, by installing them in front. It was just a bad ignition coil; as I suspected - but the plugs was half way through it's life expectancy. Spare parts -yay!!!
Remember those old spark plugs that only lasted 20K-30K miles??

 

First time removing the cowl, is a super pain. Now, it takes 10-15 minutes at most to take off the wipers, plastic cowl, wiper motor assembly, and metal cowl using an impact driver with an extension.

Once you have the cowl out of the way, be very careful around the bottom edge of the windshield. It wouldn't take much to break it.

 

LoL; I could've done it in a quarter of the time it took him - but he had to whine and I had time and wanted to drink beer. It was a tough week at work and had to burn my Saturday..... LoL - Hint: don't whine when a friend volunteers to help you out on their weekend.

 

Some people whine if you hang 'em with a brand new rope!