Code P0135

Hi Lucy,

This codes come up when the heater of the sensor is not working and the sensor needs to be replaced. here is a guide to help walk you through and the location of the sensor in diagrams below. The air/fuel ratio (A/F) sensor also known as a front oxygen sensor (Bank 1 Sensor 1) is installed in the exhaust before the catalytic converter.

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor

You will need to clear the codes when complete.

https://youtu.be/ahK_eucFi-k

Check out the diagrams (below). Please let us know if you need anything else to get the problem fixed.

As far as the oil issue goes please start a new question please.

Just to add, a visual inspection might reveal just a broken or melted wire, because of where the oxygen sensors are located they are subject to to a rough environment I've seen oxygen sensor wires melted to the exhaust causing the same code in the past, so a visual inspection is important. The heater circuit wires are almost always 2 white wires going into the oxygen sensor. This code is for the front oxygen sensor, so that's the one in front of the catalytic converter. Check the whole wiring harness around the sensor.