Electronic Level Control for 1984

[Guest CAJUNRIV]

Recently my battery was dead. I recharged the battery and drove the car to my local mechanic for a look. They did a load test. They found that when they disconnected the electronic level control compressor the load (or what ever it was) went away. Apparently there is something associated with the electronic level control compressor that is constantly drawing down the battery. The ELC compressor is located under the hood on the driver's side fender. They were going to replace the part...but as expected...they couldn't get one from the local Buick dealer. Can these ELC compressors be repaired? If so who might do that? I understand that its function is to provide compressed air to the rear shocks. I drive the car with it connected and I disconnect it when I shut the car off to prevent draining the battery. How is ELC compressor related to the "car is leveling" message on the electronic dash board? When the ELC compressor is connected the message does not stay on long. However, when it is disconnected the message remains on much longer. I have never heard the compressor run. Can I do an "on car" test to see if it actually runs? I know...lots of questions...comments are appreciated.

[Rivieraman]

I would say you have a leak in the system.............. It is not the compressor. Have the rear shocks checked. use a spray bottle with soapy water and spray the compressor and see if the leak is bad on the compressor. I had the same thing and i replaced the rear shocks and it fixed itself

[Guest CAJUNRIV]

Interesting...I looked through my maintenance records. I found that in 1998 and about 68000 miles ago...I had a similar problem. The records show that the compressor, both shocks, and a sensor were replaced. Should I be able to hear the compressor run? If the engine is idling...I imagine the engine noise would drown out the sound of the compressor. Does the compressor run even if the ignition is off. I don't fully understand how that system works. Can you enlighten me?

[RivNut]

The compressor is wired to a BAT terminal, not an IGN terminal therefore, it will run any time the shockls let the car settle. My contention has always been that the compressor should be wired to an IGN terminal and the compressor can raise the level of the car after the car has been started. As your car sits now, if the shocks are leaking some, the car will continue to level itself everytime the sensor senses it's too low. This could go on in cycles all day and all night and unless you're right there with the car, you'd never hear it.

On my '84 Convertible, I installed a new set of aftermarket shocks and used a Monroe kit to adapt the OE system to the aftermarket shocks. It worked fine after that.

On my current '85, I've got aftermarket shocks that are not connected to the compressor, but are filled with a valve that's behind the license plate (all courtesy of the previous owner.) They're fairly new and they still lose air; I have to manually air them up about every two weeks. My battery was still running down and I discovered that even with the ground wire to the compressor pulled, there was still 12V going to it. ????? I could tell this because when I'd take the battery out to recharge it and then reinstall it, I would hear a clicking noise coming from the compressor. I've since disconnect the 12V wire and my battery stays up now.

Jason Pruitt is the ROA's tech advisor for the 79-85 models and I know that he's had lots of "experience" with the leveling system. I'm sure that he'll chime in here soon.

Ed

[Guest CAJUNRIV]

Good...I now understand that the compressor might run intermittently through the day and night as the car sits...because it gets its power directly from the battery. I agree with your point on battery versus ignition. I have heard the "clicking" noise that you mentioned as I would connect the battery. I did not know exactly where it came from, but I knew it was from the opposite of where the battery was located. So...if you just happen to lift the hood at the time when the compressor is running...you can actually hear it running? The only thing that I will hear when the ignition is off is the groaning sound when the "car is leveling" light is on. That of course happens at times when I get in the car. Would the compressor be running then? Maybe I can test that by having someone get in the car while I have the hood up and listen for it.

[RivNut]

With the car not running, open the hood so there's no sound insulation then go sit on the rear bumper. Given enough time, you'll feel the car rise (because you're outside the fulcrum rather than inside it, the rise will be much more evident.) You can feel the rear end rise and hear the compressor simutaneously. The growl is the compressor.

Ed

[Guest CAJUNRIV]

Ohhhh...yeah! I ran the test. Like you said the growl is the compressor. I have a feeling the "drawdown" is from the compressor and not due to intermittent runnning...because, I never hear the compressor running (ie. growling) while the car sits. The car sits covered in the carport. I am outside the house frequently enough (I am semi-retired) that I would think I would hear it running. But, I have never noticed that sound. I guess these compressors/solenoids can't be rebuilt.

[Rivieraman]

I have found that all compressors leak some what!!!!!!! replace the rear shocks and that will help. If you want to stop the system from workign all together and put aftermarket shocks with a manual fill nipple jjust remove teh relay located on the Convenience center it is the small silver one

Jayson Pruitt has worked with great deal and aggavation to get a compressor to not leak down. I have 3 85 Riviera's and they dont run my battery down and i let them sit for long periods of time. I think this is a great system and would hate to see it bypassed.

The rear shocks have rubber gaskets in them and they can tear from a pot hole, dry rot, causing them to leak witch like Ed said they system will run when the car goes down.

[sosuzguy]

Yeah let me get finished with company and I'll do a full reply. Just finished changing out a heater core and got rid of a cracked dash on one! WHAT A JOB..... I also have a dummy flashing security light that comes on with key off...(LED)

[sosuzguy]

Sorry for the delay in my response. It sounds like the windings in your ELC compressor motor might be bad causing this problem. If you aren't hearing your compressor kick on frequently when the car is just sitting then it's not an air leak running the battery down.

Yes your compressor can be rebuild but not by many that I've found. You can call Suncore and talk to Kenny. Tell him you have an 85 Riv and you'll need one for the later model Buicks, the ones where you can actually take the brackets off of them and then put your brackets on so it will mount correctly. Of course you will have to adjust your wiring connections accordingly. Your other options is ELC compressors from newer GM models (Cadillacs and Buicks, mostly) Same senario you'll have to look for the ones that look just like yours except they are mounted vertically instead of horizontal and switch the mounting brackets. Last case is buy an aftermarket replacement for a newer GM model from Arnott and have a bracket made to mount it vertically. It can be done but it's tedious. I have one done like this.

The "Car is leveling" light will only come on when the heigth sensor detects that it needs to turn the compressor on. That's why when you have the compressor unplugged it just sits there with the light on, the height sensor is still sending a signal to the relay to turn on the leveling light and the compressor.

The clicking noise you are hearing in the ELC Compressor area when you connect the battery is the exhaust solenoid opening and closing once. Most all solenoids on these 80's models will do a cycle when they first get connected. BTW the ELC system is on the BAT side not the ING side because: (example) after you get home, turn the car off and take your groceries out of the car -- the car is keyed off (IGN-has no current) and at that point it needs to exhaust air to re-level the car. But I agree somewhat with Ed -- I think the height sensor and exhaust solenoid should of rather been on the BAT side while the compressor should of been put on the IGN side)

The service manual test for the system is pretty much this:

1) put a load in the trunk or backseat

2) turn the key on (don't start it)

3) put the car in reverse. This resets the timer delay function to make it immediately levl.

It should kick on and pump up the shocks provided you've added enough weight to the car and everything is working

After the compressor has went off take the load out. Then you should be able to listen near the compressor area and in about 15-30 seconds you'll hear the exhause solenoid letting air out.

I have photographed various compressors when I took some apart. Including the aftermarket one. http://home-and-garden.webshots.com/album/575292584qogxoX

Hope this has helped.

Edited November 9, 2010 by sosuzguy
spelling (see edit history)

[sosuzguy]

After thinking some about this it sounds like your height sensor could be running the battery down too. I have the scans for this system if you or your mechanic need them.