Low idle revs
 

Hi a few months ago I was lucky to pick up a Mazda 2 1.5 skyactive registered 2016 with 2083 miles it's been running great untill this morning started ok no problems I went to fuel up and whilst waiting for a pump to come free I felt vibration through the car when I looked at the rev counter it was fluctuating I did have the air con on and I know that on some cars it raises the rpm when it kicks in although I have never noticed it before on this car and it is very noticeable now as the rev counter rises whe the air con kicks in and falls when it kicks out.
i have friend that works for a motoring organisation that has access to a computer when plugged in it shows no faults logged.
The idle revs seem very low, on the computer it was idling at 560 rpm fluctuating to 530 rpm this seems low to me and it gives the impression it is misfiring ( maybe it is) you can see the engine vibrates.
Can someone please let me know what the idle revs should be? Any any ideas to what is happening/ fixes would be greatly appreciated.

thanks.
the car seems to drive ok when moving along.

Miss fire would be ECU =DTC

The RPM is with AC is not out of range.
Without more diagnostic detail form a qualified source in Diagnostic tool I would have a look at the spark plugs. Please don't tell me how many miles are on them. The description first thoughts indicates an increase in the ohms of the plugs the coils raise time is adequate or you would have a DTC. Then we can talk about pintle lagging in an injector caused by a varnish that can also cause low RPM operation at idle with no DTC.
If your throttle response is sluggish and MPG lower then normal pull a plug. Or just change them Champion copper are about 2 bucks each and will more then do the job .
If an injector may be a problem then it may take more diagnostic work to determine a single or more injectors having an issue. Dump a quart of *Xylene on a full tank of fuel that will have an almost immediate cleaning effect as well increases throttle response and over all performance. But dont get spoiled using it all the time is expensive.

*if you are not comfortable in trusting that this chemical will not harm your engine or others that have no idea what I am talking about by all means dont use it! LOL
I keep at least a gallon around all the time and have used it for a few decades! but that's just me what do I know? lol