Active Cabin Noise Suppression 2008 Volkswagen Gli Electronic Valve Timing. The sound is a rattle that is heard just after the engine is started. Could it be the purge valve or anti shudder valve?
In fact, when my compressor internal bearing went out it was significant enough of a noise/vibration that one of the first things I did was to check the timing belt to make sure things weren't wonky. When the engine shuts down, so does the feed to the solenoid, allowing the actuator to move to the fully advanced position, locking a pin and ready for the next engine start. VW and other car companies - VVT (variable valve timing) if you think Toyota developed it, wrong again.
This replacement engine variable valve timing (VVT) solenoid is precision-engineered to match the fit and function of the original VVT solenoid.
It does increase w/ throttle, but not proportionally - it just speeds up a bit.
The first experimentation with variable valve timing and lift was performed by General Motors. Returned to dealership for vibrating noise. Does this happen often and does anyone know what that noise could be?