07 Murano high idle speed and P0507 code

[eric stevens]

History--
07 Murano S bought used about a month ago. It has idled high from the beginning ~900 to 950 range sometimes a little higher but no SES light or codes for about 2 weeks. Idle speed above is in drive with A/C on. No A/C and idle drops below 900 and as low as 800 but no lower than 800. Car drives and performs well with Ok mileage of about 19.5 combined mileage with 75% highway and average highway speed of 75 mph.

Removed intake silencer and tubes for access to firewall and saw that throttle body was dirty so I removed it from the manifold and cleaned it carefully with solvent and a rag. Reinstalled it and idle was very high at 1500 rpms or more and had SES light and several codes.

Did relearn for pedal position, throttle closed position, and Idle air volume relearn with methods found on internet. Got better almost back to where it was before cleaning the the TB. SES light and code P0507 again after about 2 days, idle was up a little higher than 1000+ at times. Repeated all the relearn procedures lasted another couple of days and then SES and P0507 again with 1000+ idle at times.

Did relearn again but disconnected 2 fuel injectors so that idle would be at lower speed during relearn which attained an idle speed of 650 rpm. Reconnected injectors and idle was 800 all accessories off in park. Idle speed in D with A/C on went up to 900 - 950 range and so far no SES light in last day and 1/2.

Dealer service writer and technician offered up no useful advice just that sometimes IAVL does not work right when done with out consult 2 and they would do the consult 2 relearn for me for $110.00

Questions--

1- I noticed that the TB butterfly did not close all the way. Is there a specified amount this should be open when in the fully closed position with wiring disconnected?

2- Is the threaded adjuster with lock nut on the bottom of the throttle body a throttle stop position adjustment?

Thanks for any and all input and help

Eric Stevens