A little history. Came out from work one day and car was slammed after getting a few "check air suspension" lights. Took it to a repair shop. Bought a complete new compressor with dryer assembly. Front finally raised, back did not. Told to buy ride height sensor, rear. Shop installed, still no air in the rear bags. Front aired up fine. Any suggestions? Dying to get my car back, been two weeks.
'98 LSC Rear bags won't inflate
- Thread starter skelley
- Start date
driller
El Presidente
Welcome! 
Sounds like the shop is throwing parts at it... at your expense.
Some insights... the "check air suspension" warning is a sign something went wrong. Often left unchecked, the problem will worsen often overworking the compressor which will then require replacement.
But since the compressor has now been replaced, it is possible the original problem is still prevalent.
The front airs up first, then the rear. (It appears the front has raised but the rear has not, even with a new compressor and height sensor.) The system should run the compressor for up to 90 seconds in an attempt to raise the suspension to ride height.
If the check air suspension warning comes on immediately or within a few seconds of starting the car, the system has detected a hard fault and will quit. If the system 'times out' before the suspension has raised, the check air suspension warning will come on. This is usually indicative of a weak compressor or a leak - in the lines, solenoids or air bags. The system does not have enough reserve volume to make up for much of a leak, so it is likely any significant leak will not allow the air bags to inflate.
You may be able to assist in the troubleshooting by jacking the rear of the car up slightly (but below the full ride height) and try to let the car air up. Sometimes that will allow the system to air up but will not necessarily mean it's fixed.
When it does air up, one of the better health checks is to turn the suspension switch in the trunk to "off" and see if the suspension stays up overnight. If it does, try driving it and see if the suspension stays raised. You will often isolate a leak in doing this.
Sounds like the shop is throwing parts at it... at your expense.
Some insights... the "check air suspension" warning is a sign something went wrong. Often left unchecked, the problem will worsen often overworking the compressor which will then require replacement.
But since the compressor has now been replaced, it is possible the original problem is still prevalent.
The front airs up first, then the rear. (It appears the front has raised but the rear has not, even with a new compressor and height sensor.) The system should run the compressor for up to 90 seconds in an attempt to raise the suspension to ride height.
If the check air suspension warning comes on immediately or within a few seconds of starting the car, the system has detected a hard fault and will quit. If the system 'times out' before the suspension has raised, the check air suspension warning will come on. This is usually indicative of a weak compressor or a leak - in the lines, solenoids or air bags. The system does not have enough reserve volume to make up for much of a leak, so it is likely any significant leak will not allow the air bags to inflate.
You may be able to assist in the troubleshooting by jacking the rear of the car up slightly (but below the full ride height) and try to let the car air up. Sometimes that will allow the system to air up but will not necessarily mean it's fixed.
When it does air up, one of the better health checks is to turn the suspension switch in the trunk to "off" and see if the suspension stays up overnight. If it does, try driving it and see if the suspension stays raised. You will often isolate a leak in doing this.
Last edited:
BlackIceLSC
New member
Yep...JP nailed it (Driller)
try jacking up the rear of the car slightly to "help" lighten the load the compressor has to lift to see if the air is actually trying to fill the bags.
knowing WHEN the system sends the warning will help US help YOU
also...you need to make sure the shop has installed rear ride height sensor and adjusted the sensor mount in the correct location.
If they removed the upper L-shaped arm and re-installed it in the wrong position, the car will think it's already 'raised; and not fill the rear.
click this link to help you better understand the problem:
http://www.markviii.org/LOD2/asexplained.htm
and this link to understand how the ride height sensors and their position controls the ride height
http://www.markviii.org/LOD2/sensorlowering.htm
try jacking up the rear of the car slightly to "help" lighten the load the compressor has to lift to see if the air is actually trying to fill the bags.
knowing WHEN the system sends the warning will help US help YOU
also...you need to make sure the shop has installed rear ride height sensor and adjusted the sensor mount in the correct location.
If they removed the upper L-shaped arm and re-installed it in the wrong position, the car will think it's already 'raised; and not fill the rear.
click this link to help you better understand the problem:
http://www.markviii.org/LOD2/asexplained.htm
and this link to understand how the ride height sensors and their position controls the ride height
http://www.markviii.org/LOD2/sensorlowering.htm
Last edited: