One problem related to engine noise has been reported for the 1998 Volkswagen Beetle. The most recently reported issues are listed below.
When cruise control was engaged vehicle would suddenly accelerate beyond the set speed. The dealer examined the vehicle, and found that the throttle control module was defective. The vehicle's speedometer would not go past 60 mph. The a/c compressor failed which caused a loud squealing noise when turning the a/c on. The mil light illuminated intermittently. The dealer replaced the air hose , air pump and mass air flow sensor.