2000 deville suspension

[Danny32687]

so i've seen threads about my similar problem but they were for older models. i have 2000 deville and my rear end is sticking up about 4 inches then normal and it has made it very stiff to drive. the compressor works cause i always hear it turn on when i get out of my car, but for some reason it wont level off. what can cause this problem? and how do i fix it myself? please help!

[JimD]

We always need trouble codes ("DTC") to point you in the proper direction. Read post #2 at this location to display your codes http://www.cadillacforums.com/forums...s-warning.html

You are interested in C prefix codes for this situation. And it sounds like your Electronic Level Control exhaust valve might be causing the problem.

But we need the codes first.

[Danny32687]

i already checked the codes. there are no current codes, everything is all history

[chubbyranger]

History codes can still lead you to the problem since some do not remain current once the ignition is cycled. Could be that the level sensor switch is not shutting the compressor off, possibly a bad switch or dirty contacts. In that case the compressor could run until it times out. Does the back end cycle up and down or does it always sit ass high?

[Danny32687]

it's always up high.

[JimD]

Dump the the air pressure by removing the air line attached to either one of the shock bags.

Then let the compressor do its test cycle at KEY ON. If the back end stays up, you will eventually get a code.

[Ranger]

Sounds like a bad exhaust solenoid valve. I'd expect one of the following DTC's.

C1737 - Exhaust Solenoid Valve Short to Battery
C1738 - Exhaust Solenoid Valve Short to GND

[Danny32687]

so i checked the codes. i have two current codes AMP U1000, and IPM B0429. but i also have a crap load of codes that say history.
amp b1004
amp b1327
ipc b1004
ipc b1327
i[c b1438
ipc u1192
ipm b1004
pcm p1106
pcm p1599
pcm u1192
rcc u1000
idk if any of those matter. also shouldnt i get a check engine light for those 2 codes that are current?

[Danny32687]

Originally Posted by JimD

Dump the the air pressure by removing the air line attached to either one of the shock bags.

Then let the compressor do its test cycle at KEY ON. If the back end stays up, you will eventually get a code.

i did dump all the air pressure but it went back up. i drove around for about half hour but still no new code beside the ones i just posted. and i got those codes before i dumped all the air

[Ranger]

Check the actuator/sensor under the rear end. The linkage arm may be bent, broken, disengaged.

[Danny32687]

is it under the driver side?

[Ranger]

I think it is on the passengers side.