Anyone well versed in the rear air suspension on the 2006 Buick Lucerne? I reckon there to be slow leak in a line, connection, and etc. The rear of the vehicle never seems to have sagged from sitting, but every time the car is started the sound of a compressor seems to run for 15-20 seconds and cut off. Then while driving the same sound can be heard off and on occasionally. I dunno. I’ve had the car off the ground on jack stands, rolling around trying to find something, but no luck yet. The sound of a compressor appears muffled like it’s inside the trunk or behind the rear seat. I haven’t found it yet. Is this a common issue on this car?

 

That initial run-up is normal. NO concerns. Consider it an advisory that the system is working.

Whenever the car is operating, if the rear lower control arm is depressed, as in parking with that wheel on a rise, the compressor will run to raise that lower control arm to its normal position. When back on level ground, it'll bleed off enough air to put the car back level. "Automatic Level Control".

 

Thanks the response and information. I apologise for the late response.