idle air stabilizer valve

[bones]

1989 525I m-20.should the engine have an increased idle speed and then decelerate on the first start of the day?mine simply starts and idles at 750 rpm.i do live in the high desert and its summer so the coolant temp probably dosent drop below 70 degrees faranheight even after sitting all night.also the valve does hum and vibrate slightly in position #2 ignition.when you pull the electrical connector off there is no increase in idle speed. any advice? thanks bones

[Morgenster]

1989 525I m-20.should the engine have an increased idle speed and then decelerate on the first start of the day?mine simply starts and idles at 750 rpm.i do live in the high desert and its summer so the coolant temp probably dosent drop below 70 degrees faranheight even after sitting all night.also the valve does hum and vibrate slightly in position #2 ignition.when you pull the electrical connector off there is no increase in idle speed. any advice? thanks bones

Could be normal unless it happens on a cold night. Normally idle jumps to 1200-1400 and then settles to 1000-900 and then later to 750-650, but for me temperatures are mild to low. And I also get the vibrations sometimes.

[bones]

thanks Morgenster,my habit of fix it till it breaks is terrible sometimes.ill put a bag of ice on my thermostat housing and drop the temp to as cold as i can get it and see if it changes the function. bones