air ride suspension problems

Probly just a leak in a hose. I replaced my compressor and hoses w after market parts (not gm) for 350.my quote for gm parts w labor was$ 1200. Solved all the problems. U can get a spray bottle w soap and water and find the leak if u just want to get out a lil cheaper. Its worth paying to get it done. Do have to say it looked sweet when the bags were empty.if u live in tx I can get u in w my mechanic he does good work and he olny had my denali for 24 hrs.

The rear air bags have been acting weird for a while now, it started out only going down at night, but then it started going down all the time, even while driving, and now they wont even come up at all.. I didn't know what to do, money is tight right now but I can't stand bouncing around all the time while driving.. I didn't know if there was an alternative to the air bags, like if I could get something cheaper that basically does the same job? Anyways I would really appreciate any advice you could give me... Thanks

9 times out of 10 it will be the air bags that are leaking. It could be a leakage somewhere and not necessarily a fault with the air spring itself.

Thanks, I'll try that :)

You're welcome.

If you need to replace the part, check out this link. Part is sold in pairs and if one fail, the other might not be far away. $87.00 each

https://www.amazon.com/gp/product/B07CXZN2TP/ref=as_li_qf_asin_il_tl?ie=UTF8&tag=2carprcom-20&creative=9325&linkCode=as2&creativeASIN=B07CXZN2TP&linkId=b0d252e67c4e30b814deb9085c023a6b

The rear of vehicle has dropped almost to the ground. I can hear the compressor running but nothing happens. Could the compressor be worn out enough that it still works but not strong enough to air the suspension up? Dealer says i need a new compressor and air bags which is fine just seems odd that i can hear compressor running .

Hello,

Since can hear compressor running first thing I would do is crawl under find the compressor then check the hose connects then follow hoses to make sure they are intact and also listen for any air leaks and check the air bags for damage.

Thanks i will get under there and look it over for anything obvious. On the air outlet in the cargo area the gauge says i am getting a little over 30 lbs of pressure from the compressor. If that helps.

While I don’t think it’s relevant, I noted that one of your other members reported that their air bag problem started just after the battery went dead. In my case it was 3 days after replacing the original battery.
The problem is that, with increasing frequency, the air bags go flat over night after parking the Envoy at home. If it makes any difference, it’s an XUV model. The dealer has checked the fittings for leaks and found nothing. In fact, for the two days it sat at the dealership, the rear height changed only slightly up and down due to temperature changes. When I brought it home last Friday, I left the key on and stood on the rear bumper to force the leveling system to operate. Once I got off, it settled back to what seems to be the normal ride height. It stayed fine until Saturday evening when I drove it around town on an errand. I parked it this time and just turned key off. The next morning, it was down over two and a half inches on each side. Any ideas on what to look for? I know that it has 3 solenoid valves. One for each side, and one to relieve pressure when the pump starts. Any chance one of the bag valves is hanging partially open and deflating the system?

Sounds like that is exactly what is happening.For it to sink the same amount on both sides it might be the motor bleed off valve that is letting it out, it would be quite a coincidince for the left and right valves to stick at the same times

Seems like both left and right valves would have to be sticking for the motor bleed off valve to cause the problem. If I understand the system, the pump output goes to a "header" from which pressurized air can go to the left or right air bag if the left or right solenoid is open, or to the inflation station inside the back of the vehicle. The inflation station has what looks like a regular tire schrader valve. The third solenoid valve briefly releases the pressure from the "header" so that the compressor isn't starting against a load. Once the compressor is running this third valve closes. My main point here is that, if I understand the system correctly, that the third solenoid (motor bleed off valve) is in parallel with the 2 solenoids controlling flow to the air bags. It does occur to me that I don't know where/how the system bleeds air from an air bag to lower a side after the load is removed from the vehicles. Any other thoughts?

My software is very vague about how this system works....... Does the inflate switch light ever blink? If so count the flashes, these are codes for the suspension system. I would figure that the left/right valve would open to allow air to be dumped, as to where it releases it, all Mitchell mentions is an exhaust valve that dumps pressure. There are a few TSB's (tech service bulletins) on diagnosis of the rear system. Check the main connector for loose condition or poor pin contact. Always support the vehicle when working with air bags

I have a 2004 GMC Envoy Slt. The rear air suspension is not working. Compressor is running and attempting to fill, but nothing. Took it to be checked and the tech found nothing. He 'reset' ? it and then it worked fine....until the next day. It is doing the same thing. No codes popped up and no leaks were found. What could it be?

It most likely has either a bad compressor or a leak and the module is sensing that and shutting the system down. With the right scan tool there should be codes that you can retrieve.

Suspension problem
2003 GMC Envoy V6 Four Wheel Drive Automatic 75000 miles
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My 03 Envoy air compressor will not inflate the air suspension. The accessory outlet for the compressor is producing about 31psi. The rear end is sitting way down with a little bit of air in the shocks but will bottom out easily. I don't think it is a leak as this is the second time this has happened. The compressor comes on for about 30 sec to 1 min at startup but no increase in ride hight. the last time it happened i parked with one wheel on the curb, re-started the engine and when the compressor kicked in I raised and lowered the back end by lifting on the trailer hitch. this inflated the airbags for about 2 months. The most recent drop in the suspension coincided with a dead (bad) battery. the battery has been replaced. Is there an overload reset? as the symptoms mimic what the manual says the suspension will do in the event of an overload.

Hi, my 2003 Envoy has the exact same problem. Dealer informs me, the pump is shot. Did you find a solution for yours? Very curious what the root case was.

I just repaired one. The compressor has two parts: An electric circuit board with solenoids that route pressure to whichever side is low. Nothing goes wrong with any of the electronics or electric motor. And it has a trunk air compressor. Both are powered by a single teflon ringed piston spun by an electric motor. The part that goes bad is what's actually the connecting rod bearing. In this case it's a needle bearing. It disintergrates and particles of steel get trapped between the

Teflon rings in the aluminum cylinder. The whole assembly also goes off center with all the sloppy movement that interrupts the way the piston inhales. Mechanically, it keeps working because the motor still spins the piston, although very sloppy and destructive until the plastic rod shatters. So don't keep turning it on from the trunk, you may be able to save it. I actually repaired mine by buying a pack of two 9/16 plastic hole plugs at Lowe's for .99 cents. I drilled a 9/16 hole through where the spun bearing was and plugged it with the two plugs, one on each side. Then melted in a 6mm deep socket from one end, leaving the other end closed. (The 6mm deep socket with 1/4 in. drive is exactly 12mm) Pushed in two new needle bearings (6mm Inner Diam. and 12mm Outer Diam.) Loaded it with some grease and reassembled. *Some advice: Don't use the compressor from the trunk. This is a very expensive setup for the air suspension, so if you need air, go to the gas station or use another compressor at home.

I am trying to do the repair listed above but I don't understand the steps.

Did you completely disassemble the compressor?? how did you get the electric motor disconnected from the pump body??

You also may want to check the sync of the inflation system, watched a guy at work sell the compressor and shocks to someone and it was just out of calibration.

I currently have the SUV in the dealership because the rear air ride suspension keeps dropping about 2 1/2 inches after the car sits for about 3 hours. The suspension drops evenly on both sides. Initially the service dept told me I needed to replace the air bags and the compressor, but the leak still occurs at the same rate after the items were replaced. They have checked for errors in the computer system, but nothing comes up. They tried re-setting the system, but that didn't work either. Now I am being told that a certain amount of droppage is expected, but I have had the car for 6 years and this is the first time this has happened.

Any ideas on what this might be?

-Sounds like its leaking somewhere or a problem with air suspension leveling sensor-

Yes, it has a leak and it sounds like the dealer just jumped to the wrong conclusion and didn't check it out thoroughly enough.

I had a similar issue, that was a leak at the connection between the compressor and accessory output in the cargo area.

Suspension problem
2003 GMC Envoy 6 cyl Two Wheel Drive Automatic ~60000 miles
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This is an odd problem for me in that the problem is not persistent. We have the load-leveling package with the air suspension. What is happening is that we'll come back to the vehicle after it's been sitting, and find the rear air bags completely deflated, with the rear end completely lowered. But after we put the keys in the ignition, it will inflate just fine and ride just fine. The compressor doesn't have to turn back on (to re-inflate) while we're driving it. It seems to hold air.

Now the odd part. We can leave the vehicle sit for DAYS, and it doesn't deflate a quarter inch. Yet other times, we can come back in a hour and it's completely deflated. I have NEVER seen, or heard it losing air. But it obviously does, as I said it can completely deflate in an hour. Originally, this happened once or twice a week. Now, it's about 5-7 times a week, so it does appear to be getting worse. I'm thinking of putting a webcam on it overnight so I can see if it's a gradual or fast dump of pressure.

I can't understand what could be wrong where it would retain air indefinitely sometimes, but other times completely deflate, like the system purged air.

I've done a quick check for leaks, and didn't find anything, but didn't have much room under there. I plan to lift it and try again. But I need more ideas.

Help!

That describes my car exactly! About a year ago, I had the pump replaced, and I don't want to do that again. It is a sporadic problem, but it is occuring more frequently. And I don't think it is a leak because it does not happen all the time. Did you find a solution?

this is the same problem I have with my 2002 Envoy

Suspension problem
2003 GMC Envoy V8 Front Wheel Drive Automatic

I think the problem is the rear air suspension. How long is the manufacturer warranty on air bags?

you didn't put how amany miles you have but it's out of warranty by now. there are other replacement bags @ about $130 each if you plan to install them your self.

when I arrive in morning the car is sitting down with air shocks deflated, but not always, just every now and then, seems to be getting worst...

All 4 are low? Could be a stuck bleed off valve or relay doing that. Might need to have the BCM scanned to see if it has stored or seen any failures in the system.Also look for any obvious physical damage to the air bags

only the rear two shocks let the air out, but sporadic, what is bcm, and no there is no visible damage. Have had three mechanic try and find out what the problem is and they could not. Also cruise control is sporadic...is there some computer/board that could be malfunctioning?

BCM is the Body Control Module. Have it scanned. Pretty sure the valves are on the motor for the rear shocks, most likely the valve or motor itself has a slow leak.Might need to go to the dealer for this one, they will be more familiar with the common problems of your vehicle

I am having the exact same problem with my envoy air suspension that has been previously mentioned on the forum - the air bags will deflate after one hour or after two days but reinflates when you start the car! No pattern at all - and it seems to bother my neighbors - my car looks like a clunker when in the deflated mode.

My software is very vague about how this system works....... Does the inflate switch light ever blink? If so count the flashes, these are codes for the suspension system. I would figure that the left/right valve would open to allow air to be dumped, as to where it releases it, all Mitchell mentions is an exhaust valve that dumps pressure. There are a few TSB's (tech service bulletins) on diagnosis of the rear system. Check the main connector for loose condition or poor pin contact. Always support the vehicle when working with air bags

My air bags keep deflating when the vehicle sits for over 2 hours. Yesterday it actually lost pressure while I was driving it. What would cause the bags to lose pressure?? Are the bags, air line, or the compressor leaking??

I have the same problem. My bags deflate when car sits but not every single time. I discovered that there is a leak. I have caught my truck deflating and can hear a hiss noise as the air escapes. I looked under the truck and looking at the bags, the bags look old and may have a hole or two in them maybe not big enough to see but u can see a lot of wear on my bags. When I start my truck up it inflates to normal height. I also ran into driving my truck on a long trip and the bags letting the air out as I drive. This is due because the compressor keeps putting air in and air leaks. The compressor can only run for sooo long before it overheats and needs a rest before it pumps again. What I had to do was pull over for awhile turn off the truck and let it rest so the compressor can turn on again and pump the air. As soon as I can clear out my garage and pull my truck in and lift it up and look under it i should be able to tell where the leak of air is coming from.

Air suspension will not inflate to proper height after being replaced how many fuses in system seems to be lifting w/ left bag only. this is at a firestone dealer and they can,t quite get it right........thanks

There are technically 2 fuses in the system, the ECAS fuse in the underhood fuse block, and the 4WD fuse supplies ignition 3 voltage to the module in run position. If it is not lifting evenly, and 1 shock is not pressurizing at all, then there is a leak or poor connection. There is also a sensor calibration procedure that is somewhat involved. It doesn't show this to be needed when the compressor is replaced.