chasingradio

Posting this as I've been dealing with a Suspension Fault error for several weeks. It'll be back at the dealership for the third time today, so I'll update this thread as the issue is diagnosed and hopefully resolved in case this issue occurs to others. Of course, the D4 platform is starting to age, and air suspension issues tend to plague vehicles around a decade old.

• Error: Sudden error intermittently appears on the dash and the car feels like it's on race coilovers.
  • Error message: Air suspension: System fault
  • Behavior of vehicle when the error is present: The car will "crash" over every bump and pit in the road like it's on race coilovers. On rough roads it's undrivable. On smooth highways, it's still very rough.
• Frequency: Fastest error has appeared was after 15 minutes of driving. Slowest error has appeared was after 2.5 hours.
• Temporary workaround: Resetting the car by restarting it clears the error.
• Error message evidence:
  • Youtube video with error:
    You Tube
  • Youtube video of behavior when resetting the car:
    You Tube
  • Picture:
    
    Air suspension: System fault
    

Facts of this car:

• 2014 Audi S8
• Miles: 86,000
• Recent maintenance history:
  • July 2021: front suspension bushings replaced
  • July 2021: full 4-wheel alignment
  • July 2021: After the bushings were replaced and the alignment performed, the car would lose height slowly while parked. The car looked "slammed" on the front driver's side wheel after sitting for 1-2 days. When starting the car, it popped an error: "Air suspension: Vehicle is too low. Controlling level".
    • Fix: Audi replaced a metal hose connector in the front left air suspension that was leaking. Resolved that error.
• Audi's attempts to date to fix the new Air Suspension error:
  • September 2021: reset the Air suspension via the computer at the dealership

A8L_New_England

.
Did you read: https://www.audiworld.com/forums/a8-...o-low-3025073/
.
Or: https://www.audiworld.com/forums/sea...rchid=13536574
.

chasingradio

Thanks for the reply.

I did, and sent the links to my Service Advisor, in hopes it speeds up their troubleshooting.

Also: https://www.audiworld.com/forums/a8-...aults-2858181/

and https://www.audiworld.com/forums/a8-...fault-2987826/

since it seems it can be several items along the troubleshooting chain.

SamC115

I had a fault on my A8L air suspension aswell i would recommend the purchase of an OBDELEVEN they are one of the best diagnostic machines out there and there quite cheap that should help you out alot and my fault was the air suspension level sensor you go check that they can get seized

Albert_Swafega

I think you have a sticking/broken level sensor too, without VCDS or an equivalent you have no idea where to look, however, if you visually inspect each of the four, you may spot one that looks different to the rest.

chasingradio

Agreed. I have ordered a VCDS system for future issues (since they'll become more frequent as the car ages). For now, it's at the Audi dealership. Thankfully, I have a full warranty (MaxCare from CarMax, which rocks) so anything they find should be covered.

MP4.2+6.0

As noted, one of issues is sensor. Second is an air shock. Third is the suspension compressor. Compressors often fail after an air shock leaks and then causes them to overwork if issue is ignored. A guess is you may have the second. I say that because you don't describe symptoms as continuous like I would expect with a broken or detached sensor. Could be an air leak in a strut, and then after pump overworks it gives up with the overheat type safety shutdowns after a while.

As stated, reading codes with VCDS will give a much better answer. Sensors should show up directly. Compressor shut downs will too. For leaks, you have to infer them if not directly heard (which is rare unless huge). Dropping on one end or other of car (ride height) is the usual clue; often hard to know which side because the sway bars sort of it cover up. Pump true ups of air pressure can also cover it up unless battery disconnected or it sits for a longer period of time.

grkmspr

Hello everybody,

I'm also having this trouble. few days ago, another car hits my bumper at the parking area, after 2 km, in my car it appears suspension fault, and car gets very stiff. Also its sometimes still appears. When I turn the car off and on, the warning goes away. suspensions are working normally. (Very bad road comfort, i'm glad to experience how car rides with air suspension fault, you cant belive how it feels at the road and also bumpers.)
I check the VCDS and fault code below; it shows rear left sensor error.

I check the sensors everything looks normal, is there any cable or something in the bumper?
or
is that really mechanical error or some adaptation problems? i want to ask.​​​​​​​



​​​​​​​

OberklasseA8

How adjustable are the stock units? What type of adjustments can be made?

I would compare to the other side, make sure it doesnt have any extra play. Tug lightly..

Not sure if the bumper has a crash sensor.

A8L_New_England

.
Is it fixed? What was the diagnosis?
.