1996 Chevy Beretta Fast Idle

First thing is to have the codes read.
You have a sensor in the intake air hose (or in the air cleaner housing) that reads air temp and sends it to the pcm. The pcm uses this and other sensor data to set timing, fuel mixture, idle, etc.
The code read will tell you if that or another sensor is defective.
Also check to see if your intake hose is cracked, allowing air to bypass the sensor.
VIC wildfirev9