2001 Volkswagen Jetta Q&A
2001 Volkswagen Jetta Question: oxygen sensor
I am afraid you may have been misinformed. Code P0420 is for catalytic converter low efficiency. This will commonly require replacement of the catalytic converter. Please use the RepairPal estimator to find the cost to replace the catalytic converter on your 2001 Volkswagen Jetta. Here is a link - https://repairpal.com/estimator?car_type_id=3218 - Jim Taddei
The Diagnostic code said oxygen sensor and a long list of things it could be.
The Check Engine Light may illuminate due to a faulty oxygen sensor and/or coolant temperature sensor. Proper diagnoses will be required to confirm the fault.
The Check Engine Light may illuminate as a result of a oxygen sensor and coolant temperature se...
...y symptoms—including hard starting—can be caused by coolant temperature sensor and oxygen sensor faults.