The largest online repair guide library for every car

About us
Contact support
FAQ
Sign up
Sign in

2018 CT6 Air Suspension Sagging Overnight - Compressor Noise

0

Mark S. · rep 0 · May 22, 3:58 AM · 1 replies · solved · Question

Vehicle: 2018 Cadillac CT6 Platinum

Hey everyone,

I've got a 2018 Cadillac CT6 Platinum, and lately, I've noticed the rear end sags quite a bit overnight. When I start it up in the morning, I can hear the air compressor working really hard and it takes a good minute or two for the car to level out. The ride quality also feels a bit off, not as smooth as it used to be.

Has anyone experienced this with their CT6? I'm worried it might be an expensive fix. Is this a common issue with the air suspension system on these cars? Any advice on what to check first before I take it to the dealer?

Thanks for any help!

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 22, 3:58 AM

0

ClearTheCode admin answer:

It sounds like your 2018 Cadillac CT6 is experiencing a common issue with its air suspension system, likely a leak or a failing compressor. Here's a breakdown of potential causes and steps:

  1. Identify the Leak Source:

    • Air Springs (Air Bags): These are the most common failure point. Over time, the rubber can crack or develop pinholes, leading to air leaks. You might hear a faint hiss or see the vehicle sag on one side more than the other.
    • Air Lines/Fittings: The plastic air lines or their connections to the air springs or compressor can also develop leaks.
    • Valve Block: This component controls air distribution to each air spring. A faulty valve block can allow air to escape or prevent proper inflation.

  2. Compressor Overwork: The loud compressor noise and extended run time indicate it's working harder than usual to compensate for lost air. If a leak isn't addressed, the compressor will eventually burn out.

  3. Diagnostic Trouble Codes (DTCs): A scan tool might reveal codes related to the suspension system, such as:

    • C0575: Left Rear Damper Control Position Sensor Circuit Malfunction
    • C0580: Right Rear Damper Control Position Sensor Circuit Malfunction
    • C0561: System Voltage Malfunction (can sometimes be related to an overworked compressor drawing too much power)

  4. When to See a Shop:

    • Immediately: If the vehicle is consistently bottoming out, or if the compressor runs continuously for more than a few minutes after startup.
    • Soon: If you notice significant sagging, a harsh ride, or persistent compressor noise. Ignoring these symptoms can lead to more expensive repairs, including a completely failed compressor or damage to other suspension components.

Recommendation: Have a qualified technician inspect the entire air suspension system. They can perform a leak test using soapy water, check the air springs, lines, valve block, and compressor, and read any stored diagnostic codes to pinpoint the exact problem.

Menu

Help & account