Diagnostic Aids
WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Never solder the O2S wires.
Check An improperly installed air cleaner outlet duct. Check air cleaner outlet duct for collapsed ducting, restrictions, or a missing or plugged air filter. Check throttle body and intake manifold vacuum leaks, or damaged or blocked throttle body inlet. Check exhaust system for corrosion, leaks, or loose or missing hardware. Ensure O2S is installed securely and pigtail harness is not contacting exhaust manifold. Check for O2S contamination, vacuum hoses for splits, kinks and proper connections. Check for excessive water or other contaminants in fuel. Ensure PCM and sensor grounds are clean, tight and properly positioned. Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Repair as necessary.