High frequency test

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 1997 GMC Yukon, 1997 GMC Suburban, 1997 GMC Pickup, 1997 GMC Cab & Chassis, and 1997 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.

Engine is running.
Engine run time is at least 0.4 second.
System voltage is at least 8 volts.
Throttle position is less than 89.8 percent.
MAF sensor is at least 10.44 Hz.
Conditions are present for zero seconds.