1995 Chevy Truck

Ou might try spraying around the base of the throttle body, the gasket could be sucked in causing a vacuum leak. Caution when using flammable aerosols around a hot engine though. You can try to use water, anything that will change the leak will give you a noticeable idle change. Other option would require the use of a scan tool to see what your idle counts(unless it has isc motor), and throttle position sensor value at closed throttle.