Hi Folks, I need some advice.
I have a 92 buick roadmaster estate wagon with 204k miles on it. For
the past couple of years I have had a continuing issue with the idle
speed. Normal idle speed runs about 600 rpm in drive.
The idle speed will be about 1000 rpm in drive and about 1200 rpm in
neutral after I start the car. The high idle speed remains this way
until I stop the car, place the transmission in neutral, and let the
idle speed go to 1200 rpm. It will take about 30 seconds for the idle
speed to slowly return to a normal of 600 rpm. The idle speed will
remain correct no matter how long I drive (hours). The high idle will
return if I turn the ignition off, and restart the wagon.
The high idle speed is a bit of a pain around town since you must use
the brakes lot more. A high idle of 1000 rpm will keep me going about
20 mph around town.
I have change the plugs, coil (for another problem), replaced fuel
injectors, and most importantly, changed the idle speed air control
(twice now). I have also cleaned the spindle seat with carb cleaner
and a brush. The high idle speed eventually returns after a couple of
months. The OBD1 shows no error codes.
I am thinking of changing the Idle speed air sensor again but it runs
Does anyone have some suggestions to help me keep my idle at the
Thanks for any ideas, Dan