Thanks Willy, it doesn't appear to be missing or skipping just
throttles back to almost a stall then resumes normal idle speed.
I have a basic ODB II reader that will give you the code and reset the MIL, picked it up for the Hyundai Accident that had a slow motor on the fuel
tank leakage detector, $400 for the module or reset the MIL once a month with the $39 scanner. If it comes to the point where I'm going to need one of those BT ODB scanners I'll get one of the ones you linked for sure.
I'll see how the cleaning turns out, if the problem returns I'll most likely take it to a dealer. The local mechanic knows his stuff but like you say the dealer knows the product inside and out.
Except for the local Hyundai dealership that couldn't diagnose a faulty crank shaft sensor, but charged me $110 for the diagnosis and told me I had a minor exhaust manifold and oil pan leak.