I have had this recently and tried a few things. I tired the Toyota idle relearn, which needs to be done with the engine at normal operating temperature. There are a few YouTube videos on the subject, but not for manual cars.  I recently changed the Battery resulting the low idle speed, then later had the high speed idle. Both times used the following trick to correct the idle.  Get the car to normal operating temperature. Turn off all lights, heater/ A/C and accessories, then shut off th