I'm having troubles with a super high idle on my 1986 GN and I can't find a cause for it. I tried resetting the IAC and with the throttle blade completely closed (idle screw backed out completely) it idles at 1,700 RPMs and then cliimbs to a little over 2,000 RPMs. At this high idle it is pulling between 15 - 17 on my vacuum gauge. The first thing I did was to check for vacuum leaks. I've tried my smoke machine going in the intake tube after taking the MAF out, and I've gone directly into a vacuum line and I can't find any leaks. There is no smoke coming out anywhere in the engine compartment, under the vehicle, or inside the vehicle. I also tried spraying brake cleaner on all vacuum connections, injectors, intake manifold, and all around the TB with no change in idle. I then tried pinching off vacuum lines and also plugging off vacuum lines and still no change. Is there something else I'm missing that would cause this?