Engine making whining/whistling noise from TBI or EGR valve.
Is your check engine light on? generally a vacuum leak will trigger a DTC. Whining noises are also common with bearings such as idler pulleys and other front engine components
i have 1994 gmc truck it started to whistling noise i could not find it so i work on it more then i found it it was the gaskit in between valvlebody and intake
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