Xterra Leans Air Suspension Fault

That sounds like an issue I had with my old Audi A6. The air suspension went completely haywire. Was the car sitting for a while, or did this happen suddenly? Have you checked the compressor? Sometimes a faulty compressor can cause similar symptoms, especially if it's struggling to fill a leaking air spring.

The issue arose suddenly while driving. The compressor seems to be working; I can hear it trying to engage. Could a partially defective valve cause these symptoms even with a working compressor?

Yes, absolutely. In my case, the compressor sounded fine, but a valve on one of the air springs was leaking internally. It wouldn't hold pressure, causing the leaning and ride height issues. The bumpy ride could be from the system trying to compensate. I'd recommend getting it checked by a workshop; they can properly diagnose the valve issue.

Thank you for the insight. I took it to a workshop, and, as you suspected, the suspension air bag valve was indeed defective. The repair cost was 590€. Your comments were very helpful in understanding the problem.