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Ken Finne
Ken Finne 10/2/2012
2001 Hyundai Elantra GLS 4 Cyl 2.0L - Engine
Check engine light is on
Heater circuit sensor 1 bank 1, what is the danger of driving with a faulty oxygen sensor?
1 Answer
  • CVO
    CVO 10/2/2012
    The oxygen sensors supply the computer with a signal that indicates a rich or lean condition during engine operation. This input information assists the computer in determining the proper air/fuel ratio. A low voltage signal from one or more sensors indicates too much oxygen in the exhaust (lean condition) and, conversely, a high voltage signal indicates too little oxygen in the exhaust (rich condition). The oxygen sensors are threaded into the exhaust manifold and/or exhaust pipes on all vehicles. Heated oxygen sensors are used on all models to allow the engine to reach the closed loop faster.

    A faulty oxygen sensor due to loose connections, bad grounds, high resistance in the circuit, or opens in the circuit can cause the following symptoms.

    Related Symptoms

    Surging at idle
    Unstable idle
    Running rough off idle
    Poor fuel economy
    Spark knock
    Stalling on acceleration
    Ken Finne 10/2/2012
    No apparent symptoms, fuel economy better than factory specs, slight knock, thought this was a valve lifter. Can it be fixed myself or is a trained mechanic required?
    CVO 10/2/2012
    DIY. See this repair guiide.
    Hyundai Car 1999-05
    Heated Oxygen Sensor

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