Write-Up: Rear Self-leveling Air Shocks

It turns out I pulled a "thing" in the driver's side junction box, not the passenger side box with the fuses.  I don't know what this doohickey is called, but I've misplaced it good.  

Is it possible to move the grey doohickey for the trunk release over to the ELC as a temporary solution?  Or does it need a black one?

What is this part, and where can I get another one?  Any chance it'll be in stock at O'Reilly's or NAPA?

Other than that I should be ready to go.  It turns out I was missing a couple metal clips for the airlines, and that's why the passenger airline wouldn't snap on.  I'm not sure why the driver's side airline snapped on so well without the metal clip it needs.  Are these lines pressurized all the time?  It seems like the hard plastic to hard plastic connection would be prone to leaking.  I imagine they do leak, but are sufficient to put air in the shocks, and the shocks hold pressure on their own.

Searched Rock Auto real quick and it looks like I've been talking about the Level Control Relay, which does appear to be the same part as the Trunk Release Relay. What say you?

Level Control Relay - ACDELCO D1786C {#19116057} Main Relay GM Original Equipment; Universal Info
4-TERMINAL, GRAY, HIGH-CURRENT 280 MICRO; CODE 8567, 4 TERM, 280 MICRO, HI-PWR, W/RESISTOR, UNSHROUDED, GRAY

Trunk Release Relay -

ACDELCO D1786C {#19116057} Main Relay GM Original Equipment; Universal Info One of our most popular parts
4-TERMINAL, GRAY, HIGH-CURRENT 280 MICRO; CODE 8567, 4 TERM, 280 MICRO, HI-PWR, W/RESISTOR, UNSHROUDED, GRAY

Yes, same relay.

I drove around the driveway after moving the trunk relay to the ELC spot. The compressor didn't come on. Does the direction the relay is facing matter? I have a hard time believing the compressor is bad now. Maybe the humidity could have rusted the piston in place.

Best way to actually test it is to at least turn the battery on (you can have the car running too) and open the trunk, and put some weight in it. Typically after about 30 seconds, if all is well, the compressor will turn on. The compressor wont turn on if youre moving around because it has no time to decide what soecific ride height the car is at.

I think the direction the relay faces does matter...take a look at a nearby rely and make sure it is facing the same direction.

Jack the R wrote:

Are these lines pressurized all the time?

Yes. as long as there's pressure in the system, the lines are pressurized.

All you need to do is start the engine.  Then immediately get out and kneel beside the right side rear corner of the car.  Within 17-35 seconds of starting the engine, the compressor will run for 3-5 seconds as a test.  It will do this every time you cycle the ignition switch regardless of whether the suspension is low or not.  It will run longer if the level sensor determines the suspension needs to come up.  If you do not hear the compressor, there is something wrong with the system.  It does not mean the compressor is bad, there are other things that can be wrong.

When I bought my Riv, the system did not operate.  the back of the car was low, and both rear tires had a pronounced - camber to them, very noticeable from behind the car.  This is what made me look at the system when a friend of mine who had been following my car mentioned it to me.  At first thinking it was an alignment issue, I brought it to a friend for adjustment.  We then discovered by lifting the back end of the car, it straightened the tires out.  I then realized that the ELC was faulty.  I read the FSM and followed the trouble chart for "back of car too low".  It was slow and cumbersome and took me a few days, but it allowed me to isolate the problem to a broken wire between the level sensor and the relay under the rear seat.  Once I replaced that wire, the system worked perfectly, and has done so to this day.  Every time I start the engine, I can hear the compressor run for that 3-5 seconds, from the driver's seat, if the radio is off and I listen for it.  It is much easier to hear if you kneel beside the right rear corner of the car.  Like I said, the FSM trouble chart is cumbersome, and I found myself jumping around to different sections because it was not always clear what they were asking, but I got through it, and I would never have found that wire without doing a continuity check as directed by the FSM.  Once I verified there was no continuity between the pin on the relay and the level sensor, I used a temporary jumper wire to test if the compressor would run after starting the engine, and it did.  I then ran the wire alongside the harness and made the repair by clipping the wire at the relay and sensor, and running it as stock.  The wire I replaced was the yellow one.

What you can also do is a little trick a club member showed me.  Those relays have a gray cover that you can remove by carefully prying around the edges.  Once you remove the cover, you can plug the relay in, and use a plastic probe or something non metallic to physically trip the relay and the compressor will run as long as you hold the relay closed.  I did this just to get the back of the car up until I determined the problem and repaired it.  If the compressor does not run, then there may be another problem with a different wire or the compressor might be bad.  Using the trouble chart will determine what the problem is.  You will save time and money and possible frustration by doing so.  Best of luck.

I do not believe the direction of the relay matters. If it did, there would be some provision (different pin configuration, etc) to prevent you from plugging it in backwards.

Just a quick question, been dealing with a leak. I switched the car over to a manual kit for the time being. Even with fully new lines and after putting new ends into the elbow on the compressor side, I was getting a leak and also the compressor would come on for like 2 seconds, shut off for a few, and then com back on for a few seconds. I'm wondering if its possible for compressor itself to be leaking air through itself even though it works fine, and also could the random on-off spurts be the level sensor going bad?

My air ride is fully functional again. I heard it kick on this morning while I was closing the garage door, and after work I loaded the trunk up with 280 lbs, then sat inside and listened to the pump air the shocks up. Pretty cool!

I thought I would notice the air being released after I took the weight out, but that wasn't the case. I assume the extra pressure was let out, because the car isn't sitting a few inches too high now, but I couldn't tell the air was being let out.

stydel311 wrote:

Just a quick question, been dealing with a leak.  I switched the car over to a manual kit for the time being.  Even with fully new lines and after putting new ends into the elbow on the compressor side, I was getting a leak and also the compressor would come on for like 2 seconds, shut off for a few, and then com back on for a few seconds.  I'm wondering if its possible for compressor itself to be leaking air through itself even though it works fine, and also could the random on-off spurts be the level sensor going bad?

I'm sure it is possible for the compressor to leak. Is it the most likely source of a leak? I say no. You should eliminate all other possibilities before condemning the compressor. As far as the level sensor goes, I would conduct a visual inspection first. Look for obvious damage like a bent or loose arm. Try wiggling the arm with the ignition on and see if you can get a reaction. Again, the FSM has some great diagnostic procedures. Testing and evaluating is the way to go. It makes the difference between a mechanic and a parts changer. It's the least expensive and frustrating way to fix what is broken.

LARRY70GS wrote:

I'm sure it is possible for the compressor to leak.  Is it the most likely source of a leak?  I say no.  You should eliminate all other possibilities before condemning the compressor.  As far as the level sensor goes, I would conduct a visual inspection first.  Look for obvious damage like a bent or loose arm.  Try wiggling the arm with the ignition on and see if you can get a reaction.  Again, the FSM has some great diagnostic procedures.  Testing and evaluating is the way to go.  It makes the difference between a mechanic and a parts changer.  It's the least expensive and frustrating way to fix what is broken.

I fixed a small leak when I first put the manual fill kit on in a place that I hadn't realized could leak, the back slot of the elbow where the tube curves in. I'm going to put it back together the right way and check specifically right there to see if that's what was leaking previously. Hopefully it running all the time randomly was just a random fluke because of the leak.

Spliced new lines onto the little 6" pig tails that I used to replace the original ends that went into the compressor. Same slow leak as before I put the manual fill kit on. So I pulled that end out of the compressor and double checked the orings and put a small amount of grease on them and plugged it back in. Weighed the car down and it ran and ran and ran, finally got off and looked and there wasn't a breath of air left in them the whole time it ran. Tomorrow I will back it up on ramps, weigh it down and then spray everywhere with soapy water. I'm almost to the point of just unplugging the compressor and getting the coil over shocks and removing the air system completely.