The high idle on the R is such a common problem but as yet no one to my knowledge has come up with a definite solution (maybe there are many causes). I spent the first 12 months of ownership trying to solve this. Even went to Nissan who hooked the R up to the consult which allows the actuators to be manually controlled, we set the air bypass valave to zero % fully closed and wound the timing back 5deg and the car was still running.
Guy said it should have cut out with that much timing retard.
Anyway, you can remove the valve. I found that splitting the plenum gives you just enough room to get an allan key on the 3 bolts that hold it in place and your hand in to disconnect the 2 electrical plugs. Made no difference in my case though.
Jason[
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