No, a missing thermostat is not typically the cause of error code P0-135. This code generally indicates a problem with the oxygen sensor circuit, specifically the heater circuit for the sensor. Issues related to the thermostat may affect engine temperature and performance but would not directly trigger a P0-135 code. It's important to diagnose the oxygen sensor and its associated wiring to resolve this specific error.
The PO135 error code on a Ford F150 indicates a problem with the oxygen sensor circuit for the bank 1 sensor 1. To fix this issue, first, check the wiring and connectors for any damage or corrosion. If they are in good condition, replace the oxygen sensor itself. After replacing the sensor, clear the error code and take the vehicle for a test drive to ensure the issue is resolved.
Replace the oxygen sensor behind the engine - grey connector.
in the exhaust manifold toward the firewall its the hard one!!!
Trouble code P0135 means:O2 sensor heater circuit malfunction (bank 1,sensor 1)
02 sensor heater curcuit malfunction (bank 1 sensor1)---change front 02 sensor if need be.
That is the code fot the O2 sensor. Usually fails at or around 100k. Need to get it fixed to clear most inspections.
Trouble code P0135 means:O2 sensor heater circuit malfunction (bank 1,sensor 1)
To replace the PO135 bank 1 sensor 1 (O2 sensor) in a 2003 Toyota Avalon, first, ensure the vehicle is cool and safely elevated. Locate the sensor on the exhaust manifold, disconnect the electrical connector, and use a wrench or O2 sensor socket to unscrew the old sensor. Install the new sensor by threading it into place, reconnect the electrical connector, and clear any trouble codes with an OBD-II scanner before starting the engine.
Trouble code P0135 means: HO2S Heater Performance Sensor 1 Trouble code P0420 means: Catalyst System Low Efficiency (Bank 1)
the po420 could also be a misfire or vacuum leak
O2 sensor heater circuit malfunction (bank 1 sensor 1). You probably have a burned out Bank 1 Sensor 1 O2 sensor. Also check the wiring at the sensor for damage.
You have one of three general problems in order of most to least likely.The O2 sensor is badThe wiring or connections have an issueThe computer is bad and not seeing the operation of the heater.