I think I may have a bad o2 sensor heater. I have rough misfire during cold start, I got a code for misfire cylinder 4, and catalytic converter below efficiency. What are the symptoms of a bad o2 sensor heater.
What are the symptoms of a bad o2 sensor heater.
Check engine light. It really does not do anything with other issue you mentioned.
No noticeable symptoms, other than the error code which specificly says that your sensor heater is bad. Maybe a rougher idle during engine warm-up, but not necessarily.
Since this fault is not a critical one, I am not sure whether or not it triggers the Check engine light on all vehicles. On one of mine it surely does - been there.
If there is a problem in the O2 heater circuit that should trigger its own code like P0135 or P0141. You can use a multimeter to do a rough test of voltage in the circuit and continuity in the O2 sensor heater.
https://www.youtube.com/watch?v=YzkBdPP8l2g
best to check your fuel injectors first
mine had the htr code in the I/M test replacing the aftermarket FI's solved the problem
