What about Buick GL8 idling at high speed?

1 Check the idle speed with the computer to determine whether it is a false alarm or really high. 2. Check whether the vacuum degree of the intake pipe leaks. Inaccurate working parameters of intake flow sensor, idle motor and throttle position sensor will lead to unstable idle speed. The parameters of each sensor can be tested by computer, and air leakage of intake manifold will also lead to high idle speed!