Reviving the exhaust valve/solenoid on the electronic leveling compressor

[hjb981]

My electronic leveling system does not lower the rear-end of the car ('97 DeVille). Obviously, nothing leaks, since the rear-end is riding too high, not too low. It is not related to the height sensor, because the car does not try to increase the height more than it should if I let out the air manually by pulling the air lines and then let it re-level.

The rear-end goes up slightly with each ignition cycle, since the system briefly cycles both the exhaust valve and compressor each time the car is started. This has happened once before, and that time I replaced the compressor (I got a faulty re-manufactured one, and then they sent me a new one on warranty). The re-manufactured one was bought because my original one quit (both it and the rear air springs were leaking at the time, two years ago). As a result, I now have two working compressors with frozen exhaust valves or broken exhaust valve solenoids, and one compressor that does not run. The exhaust valve and solenoid might have worked on that one when it was removed, but of course there is the chance that it was frozen, since that would not have made any different when the whole system was leaking. I also have three air dryers (that sits on the compressors).

My question is: does anyone have experience with fixing these exhaust valves or solenoids, or any tips? I think it should be doable. At the moment, I have just let the air out of the system manually by pulling the air line at the compressor, and then I let the car level once, and then I pulled the fuse. That works temporarily.

Apart from a faulty valve or solenoid, It could also be a faulty circuit that actuates the exhaust valve, and while I intend to check that, it seems less likely compared to the valve or solenoid itself.

[rockfangd]

I feel you. I have not found much of a solution to the problem with the exhaust portion. It seems to be condensation and moisture that kill it. I have disassembled many and 9 out of 10 were corroded throughout. How are your vent hoses? there are 2 one goes to the compressor and the other goes to the exhaust, then they tie together and go up into a green part with a filter. Is that all intact? usually the hoses fall apart and allow moisture and water to enter the system. I have rerouted the hose that goes up to the body up and away from the underside of the car and have had good luck

[hjb981]

I will check the vent hoses.

If the compressors turn out non-repairable, has anyone bought a replacement compressor head? It should be possible according to the FSM. Another option would be an Arnott compressor -- new, but different from the factory design, any experiences on those? I am mostly concerned about the noise level, if it differs from the OEM compressor. Anyway, the first option is still to fix the exhaust valve on one of the compressor heads that I have.

Rockfangd, were the exhaust valves on the compressors you took apart so badly stuck that they would not come loose, or was it that the valves would not seal properly once they had been loosened, resulting in a leaky compressor?

[KHE]

All three components (compressor head, exhaust valve, and motor) used to be available as service components. The way GM is discontinuing parts left and right you would need to confirm availability with a dealer.

It is possible the circuit that activates the solenoid is not operating correctly. There should be a troubleshooting chart in the shop manual that can help pinpoint the problem.

[rockfangd]

usually nothing moves at all. sometimes the solenoid still works but the valves dont, vice versa, or both dont work