why does my 2003 buick century suddenly start to high idle
My 2003 buick century started to high idle. It has been driven that way for a couple of
days, There is no check engine light on and no dtcs were present when my diagnostic
machine was put on it, please help
Check the throttle position sensor and the throttle plate itself. Make sure the plate is clean. Also inspect the throttle linkage make sure it's not sticking, dent or dirty.
I also have a Buick Century. I removed my idle air control and carefully cleaned the tip. I cleaned the passage with a test tube brush and throttle body cleaner, then re-installed the idle air control. While I was at it, I cleaned the throttle body butterflies and opening. It works great now!