P0135: O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)
What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.
What P0135 means
This code indicates the oxygen sensor heater circuit for the upstream sensor (before the catalytic converter) on Bank 1 is not working properly. The heater helps the O2 sensor reach operating temperature quickly so it can provide accurate readings to the engine computer. When the heater fails, the sensor takes longer to warm up, which can affect fuel economy and emissions.
What causes P0135?
Is P0135 safe to drive?
You can continue driving with this code in most cases, as it primarily affects cold-start emissions and fuel efficiency. However, prolonged driving with a malfunctioning O2 sensor can lead to increased fuel consumption and may eventually damage the catalytic converter, so have it diagnosed within a few weeks.
P0135 repair cost
Industry-average estimates. Cost depends on whether only the sensor needs replacement or if wiring repair is also required, and varies by vehicle accessibility.
Which one is it for your car?
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