Two problems related to catalytic convertor have been reported for the 1999 Volkswagen Jetta. The most recently reported issues are listed below.
Check engine light repeatedly comes on due to malfunction of O2, mass air flow sensors.
Vehicle experienced several recalls/ and several problems: dome light, vanity mirrors, emissions problems, etc. . . The consumer experienced the following problems with: the interior dome lights, interior trim had come loose on the passenger side, the passenger vanity mirror light did not shut off, the cup holder was jammed and had broken, the driver window sounded as if air was coming in the vehicle, the glove compartment hinges had broken, the air bag light would come on when the radio was turned off, the sensors never seemed to work, the oil dipstick had given abnormal readings(showing low when oil was just changed), the lean oxygen sensor was replaced, the check engine light was intermittent but stayed on, and the catalytic converter was replaced due to noise which ended after the repair(the check engine light had come back on).