For rough idle rpm (petrol driven cars)
Try idle relearn procedure
Drive car and bring engine temperature in normal operating range
Then stop the car and wait for 3 to 5 min
Switch off all electronic items like lights parking lights
Sound system unplug any charger all doors must be closed domelight should be off .
Hand brake should be engaged.
Then switch on the engine but donot start car wait for
2 to 5 seconds (if abs light availble let it turn off )
Then switch off
Switch on again
Press the break pedal
Start the car keep brake pedal pressed .
(Rpm may hover up and down )
One can also engage gear with cluch pressed but keep brake pedal engaged .
wait 2 to 5 min engine rpm will find a stable point.
Congrats idle relearn procedure is complete
One can search you tube also but process is explained for automatic Corolla s only