P0135 means o2 sensor heater circuit malfunction (bank 1, sensor 1). The heating element inside the upstream O2 sensor has failed. The heater gets the sensor to operating temperature quickl
Drive gently and get it diagnosed within days.
The heating element inside the upstream O2 sensor has failed. The heater gets the sensor to operating temperature quickly; without it, the sensor reads slowly or not at all when cold.
Most common — the heater element fails with age.
Check the fuse first — cheapest fix.
Corroded connector or broken wire.
Replace the sensor assembly.
Typically $150–$400
O2 sensor replacement typically $150–$400. Estimates vary by vehicle. Costs are estimates and vary by vehicle, location, and shop.
Safe to drive. You'll see worse cold-start fuel economy and possible failed emissions. Not urgent, but don't ignore it.
Typically $150–$400. O2 sensor replacement typically $150–$400. Estimates vary by vehicle.
Drive gently and get it diagnosed within days.
The most common cause is burned-out sensor heater. Most common — the heater element fails with age.