How to disconnect high RPM when starting on 1988 4 liter?

[aussiebob]

1. Spoiler

    

    

[gogmorgo]

Excessively high idle is usually due to air getting into the engine some other way than through the throttle. Vacuum leak, bad intake gaskets, etc.

There’s also other factors that could cause it. A stuck open Idle Air Control (IAC) valve could cause a mild high idle. A throttle stuck open, either of it’s own accord or due to a sticky cable or a floor mat jamming the gas pedal can also cause a high idle. 

[aussiebob]

Thanks gogmorgo back manifold bolts where loose ,back to normal. Kudos Mate.