System Too Rich (Low Air/Fuel Ratio)
WARNING: This page does not describe the selected car, but rather 35 other vehicles, including the 1992 Pontiac Trans Sport, 1992 Oldsmobile Silhouette, 1992 Oldsmobile Bravada, 1992 GMC Yukon, and 1992 GMC Vandura Special. However, it is still accessible from the selected car via links, so may be relevant.
The idle speed will be too low. Tech 1 "Scan" tool IAC counts will usually be above 80. System is obviously rich and may exhibit black smoke in exhaust.
- Tech 1 "Scan" tool O2 voltage will be fixed above 800 mV (.8 volt).
- Check for high fuel pressure, leaking or sticking injector. Silicone contaminated O2 sensors "Scan" voltage will be slow to respond.