2001 Hyundai Elantra P0720. HT, I have the problem with my Hyundai Elantra. I saw there

Answer 1

but do suspect the connector on your output sensor may be broken and snapping in place so now it may be loose. If it was pulled out in a hurry then it's most likely loose. I've used electrical contact cleaner and diaelectric grease inside the contact pins along with zip tie'ing the connector to the sensor to secure it. And as this other guy said, aftermarket sensor are a bad option. Shoot even the factory ones dont last for ever.