2001 Hyundai Elantra P0133 Code: Diagnosis and Solutions After Replacing O2 Sensor, PCV, Fuel Filter, and More

Model: 2001 Hyundai Elantra Fault Code: P0133 Posted: 2018-11-07 07:57

I own a 2001 Hyundai Elantra and am currently experiencing the P0133 diagnostic trouble code. I've already replaced the oxygen sensor (O2), valve cover gasket, PCV valve, fuel filter, thermostat, spark plugs and wires, flex pipe to the muffler, and air cleaner. I've also thoroughly checked for vacuum leaks and confirmed there are no exhaust leaks. Despite these changes, the P0133 code persists. I'm wondering: what is the correct coolant temperature reading under normal operating conditions? What should the proper fuel pressure be? I suspect the issue may lie in sensor signal integrity or wiring, but I'd like to confirm if there are any other potential causes or troubleshooting steps I've missed.