Whittier here's a couple videos showing how to do a leak down test just in case you decide to do it on your own. As long as you have the correct parts, it's pretty easy. You can build the leak down tester for cheap (I like the ease of use of the gauge in the 2nd video. These videos came from you tube and there's plenty more over there. Go ahead and do it yourself. You should be able to get to most plugs without too much issue. You can get to 1 and 2 really easy as you already know, 3 and 4 is a pain, but if you remove the fuel rail they are easier to access and 5-8 should be pretty easy, again you may have to remove the fuel line, but no big deal removing it.

However, since you know you have to pull the passenger side heads, you may as well just pull them and take it to the machine shop and let them do all the testing, milling etc Put your time and energy into removing the head(s) , hell you may as well yank them both. No need to waste your money and time with the dealership as you already know there's a problem with at least the passenger side head. Save your money and time. Just One Man's Opinion.



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thanks. I have not decided what exactly I am going to do just yet. Since I don't have a garage this is going to wait until probably April or May (since it rains here in Oregon all the freaking time). I basically have 3 options at this point. Yank the heads and have a local machine shop rebuild them. Find some remanufactured heads and swap them out, or since it has 158K I may just swap the motor with a remanufactured one.