DTC P1133: O2S1 Circuit - Insufficient Switching: Description

Oxygen sensor responds to oxygen content in exhaust manifold. Sensor voltage is read by the PCM to determine a rich/lean O2S1 signal used to adjust injector pulse width. Normal sensor reading will fluctuate between 10-999 millivolts. DTC sets when O2S1 signal has too few switches over a certain length of time.