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$5.00 "fix" for air ride compressor....

163K views 127 replies 77 participants last post by  bbach 
#1 ·
Hi, my name is Jeremy and this is my first post. Anyway, my wife has an '02 Envoy 4wd with the air suspension in the back. Well, after sounding worse and worse, the pump finally gave out. I checked the dealer and they wanted $474.00 for a new one! Cheapest I could find it online was $370ish, which was still way more than I am willing to pay. I didn't want to get a used one, since it will probably not last too long either, giving my luck. So I figured I would take the old one off to see what I was working with. Pretty easy, just 2 13mm bolts, 2 wiring connectors, 3 (1 for each air bag and 1 for the accessory outlet in the cargo area)5/32" plastic hoses which are threaded, and 1 rubber hose for the intake of the pump which goes into the cargo area.
I pulled the ferrules off the plastic hoses, then the pieces that thread into the pump. So now I had three bare, 5/32" hoses hanging where the pump used to be. Two of them for the bags, and one still connected to a schraeder(sp?) valve in the cargo area(the one for inflating things for 2 minutes before it overheats and shuts off):rolleyes:. So I went down to a local rubber/hose supply store and bought a 5/32" union tee with push in connections. Came home, pulled the fuse for the eacs under the hood, plugged the three hoses into the tee, and taped up the electrical connectors and intake tube to keep dirt/moisture out. Then I plugged my portable air compressor into the valve in the cargo area and pumped it up to normal ride height, which was around 50psi. It works great and it only cost $5.30! Plus, I can adjust the ride height any way I want to(within reason)!
Pics to come later tonight. Sorry for the book.
 
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#38 ·
Another trial

Thanks for the information, Bartonmd. I have a "concerned" wife that wants to keep here daily driver original and doesn't want her engineer hubby to goof it up so I am investigating all options at this point.

Last night, I hooked the hitch, bike, and pop-up to the Envoy. I found that after a few compressor cycles, the truck leveled itself. I then pulled the fuse. It looks like I may get off lucky and not have to do anything until the compressor dies.

The compressor has some neat valving on it; that must have been were the cost was because the compressor itself appears to be undersized for the application. Probably why it has to cycle so often with short runs times to prevent premature failure.

Anyway, I will leave it at this and see if it works for me. Without this forum, I would not have been able to trouble shoot this condition. Thanks to all for their input. I will post a picture of the loaded XUV the next time we load up for trip.
 
#39 ·
my compressor was making real bad noises, didnt pump up truck no more,wasnt the easyest to get the compressor out to get at hoses & wires, when i finaly got it off& disconnected the lines had a buildup behind the tightning nut so i had to cut the tubes so they fit in the t union ...
gave it some air & it roseup!!!what a blessing this fix was,,,4 bucks for the t.
 
#40 ·
Failure mode?

2003 SLT intermittent even sagging of the rear suspension. Intermittent is overnight to a couple days; it used to be a week.

If the system recovers normally after starting the vehicle with no abnormal noises nor compressor shut-down, what is the failure mode? If a hose or bag was defective then the sagging failure would be consistent time-wise, not intermittent.

Is this a check valve issue? The AllData TSB posted addressed the 2002 Envoy; would that apply to the 2003.

Anyone else on their third water pump in 75,000 miles?

Newbie from Naples
 
#41 · (Edited)
Didn't work...

Well, I loaded up the bike and the camper, let the pump cycle a few times and then pulled the fuse. It worked fine; drove it around a few miles - great. Last weekend, loaded up the bike, camper, and all the gear, let the pump cycle and it would not pump it up enough.

So, I'm going to add two "tees", some hose, and two Schrader valves and see if it will work.

Will keep you posted and get pictures when done.
 
#42 ·
Didn't work II

I didn't have the Schrader valves so I just spliced tees into the two main air spring lines and teed them both to the Schrader valve in the rear compartment. This setup keeps the compressor in the loop (pictures attached). I took a short piece of line, plugged it with a screw, and plugged it into the outlet on the compressor for the air hose to the rear compartment. It worked fine under normal to heavy conditions but it still wouldn't pump up the rig fully loaded for camping (with the motorcycle carrier/hitch/popup).

I was getting a normal unloaded reading from the Schrader valve of about 50 psi. Loaded, the little compressor pumped it up to aobut 90+ but still wouldn't level it. Of course, my average shop compressor does not produce over about 80 psi so this just didn't work.

I have decided that I have an overload situation (probably due to the leverage of the carrier/hitch). The set up just creates too much leverage too far back (about 20") to lift the load.

I probably won't pursue any more modifications to the Envoy. Instead, I will go back to putting the carrier on the tongue of the pop up and moving the propane tank. This setup worked fine; just really liked the other better.

Thanks for everyone's comments.
 

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#43 · (Edited)
Well to continue resurrecting this old post I have the same issue.

2003 Bravada AWD 140K miles

The compressor was acting up (replaced a first time under warranty) and making a horrible noise for a while before I started to notice that it wasnt keeping the rear suspended normally. I still get some noise from the compressor periodically but it has given up on any movement at all in the rear. So I may try the union Tee option. If as was stated its possible to reinsert the connectors so you could use a compressor in the future it seems that this "fix" would at least do one of two things -

1. fix the problem without paying out alot for a shop to replace the compressor
2. Determine if the air springs are leaking in addition to the compressor problem

It seems to me that a shop will require you to replace the compressor before they can "determine" if the air springs leak - (another $200+ repair I'm sure)

Now for my questions: If the compressor is all thats bad I saw someone post that they were able to remove theirs without raising the vehicle. How exactly was this accomplished? It appears to me you would have to remove the rear wheel to get to it (and thus raise the vehicle at least some). Also which fuse (and where is it) do I need to pull after trying this fix?

2nd - if the air springs are leaking I guess the cheaper option would be to replace the compressor/airsprings with a normal coil spring. Do any of you have experience with this and an opinion on pros/cons (I do not tow) and in fact with 140K on the vehicle I am hoping to just eek out another 60K from her before retiring it (hence not wanting to spend much)

I unfortunately do not have much auto repair knowledge or ability so although I think I can probably handle pulling the compressor and trying the union Tee option (or a replacement compressor perhaps) I wouldnt tackle anything involving the air springs or a coil spring.

Vendor for coil, compressor, airspring replacement http://www.arnottindustries.com/part_OLDSMOBILE_Air_Suspension_Parts_yid12_pid119.html

Thoughts/comments appreciated!

Oh and does anyone know what the cost range might be for replacing the airsprings with either the same or coil springs at a non dealer shop?
 
#44 ·
If you do a search on the site, you'll see some threads of folks who replaced the air setup with traditional coil springs.

You'll need different shocks too since the shocks for the air springs are a different length than those of the coil springs.

IIRC, there's a few other miscellaneous small parts that go in, like bump stops or something. I haven't done the conversion, but the threads about it describe it as a pretty simple job. You and a friend should be able to get the job done with some basic tools.
 
#45 ·
Quick question regarding this issue. I have a 2004 Envoy XUV that exhibits these same symptoms. Usually, the suspension is down when I go out to start the car. Occasionally, however, the suspension does not deflate. This leads me to conclude that there is probably not a leak in the air bags or hoses. That would leave the compressor or one of its components as the culprit. I believe I saw a TSB on this site that describe a rebuild kit for the compressor that included a new check valve? One of my mechanically inclined friends suggested adding an external check valve in the line to the airbags as a quick fix.

Has anybody tried this?

Thanks
 
#46 · (Edited)
I haven't seen any posts about that and I searched quite a bit as I tried to research the issue. Frankly I was tired of the whole situation and I gave the Arnott industries replacement coils a try. It was very simple to install (and I'm not mechanically inclined) and their coils dont need to have the shocks replaced. It cost me about $250 for everything. You might try the check line you suggest to just see if you can skip the repair for a while or just say to heck with it and get rid of the problem forever with the coil - i notice no difference at all in ride quality although i don't tow.

Oh and a footnote - i did try to union T after removing the compressor to see if my bags where shot. Turns out they were (slow leak about 2 days to go all the way down) but I didnt want to deal with pumping it up every other day and wanted to just replace it.
 
#48 ·
No problem Crazy and I totally agree. My 2003 has about 140K miles and I had already been through 1 compressor under warranty. Plus the airsprings themselves will inevitably have to be replaced so you wouldnt be stuck with just the compressor costs for long. And given how easy the replacement was (in hindsight) I wouldnt have even considered any other option. I posted a review of the arnott coils just today in this section. Take a look and if you have questions feel free to shoot them my way.
 
#51 ·
Hi, I just wanted to say thanks for posting this. My compressor made all the right noises but didn't seem to pump any air so after a week a so of bouncing around in low rider mode I pulled it out and connected the three tubes with a union tee as you described. I pumped the bags up 6 hours ago and so far so good. For anyone thinking about doing this, I have very little car experience and this was a pretty straight forward job.

Thanks OP! :thx
 
#52 ·
This is a very thorough thread - I'll put my experiences here.

2002 Bravada 206k miles. The air compressor was replaced shortly before I bought the truck in 2009. The rear end was sagging after picking up the truck from a muffler shop that also had a Tech 2 to test my AWD module. I figured out that they lifted the truck on the frame, letting the bags "stretch out". The bags were original, so I assumed they were dry rotted and simply tore from being fully extended.

I purchased new "take off" bags from a customizer in Texas for $120/pair. I installed them...didn't go very well. I had to cut the hoses off as the fittings were severely corroded. After buttoning everything back up, I could hear the hoses leaking. I hadn't properly cut the tubes, so I borrowed a tube cutter and reinstalled the tubes. I connected a pair of couplers inline with a short length of 5/32" tubing because I had cut myself a bit short. And they still leak at the air bag fittings.

The tubing I used is more flexible than the OEM, but it's not "soft" tubing. Is it possible that the tubing wall thickness makes a difference? I'm tired of doing this...
 
#53 ·
Air bag adjustments

Although I am dating myself, my 1968 Chevelle had air bags in the rear coil springs. Both bags were fed off the same line, which ran into a "tee" then went out the back of the car beside the license plate. The final connector was nothing more than the business end of a tire valve.

Ride height was adjusted at the local gas station, where you either pumped air in or let some out as required. If you needed a work out, you could do it with a manual bicycle air pump.

A simple solution that worked for a generation. Might work for you too if the compressor craps out again.

Tobruk
 
#63 ·
Although I am dating myself, my 1968 Chevelle had air bags in the rear coil springs. Both bags were fed off the same line, which ran into a "tee" then went out the back of the car beside the license plate. The final connector was nothing more than the business end of a tire valve.

Ride height was adjusted at the local gas station, where you either pumped air in or let some out as required. If you needed a work out, you could do it with a manual bicycle air pump.

A simple solution that worked for a generation. Might work for you too if the compressor craps out again.

Tobruk
My '67 Camaro had the same set up using Gabriell Hi-Jacker shocks... :thumbsup:
 
#54 ·
check compressor first

Well ive only red the top 1/4 of this post cause its as long as the new obama health bill.
my issue is i just about replaced my compressor when my istinkts told me to check it. and thats what id intended to do untill i seen this post. but anyways i figured out how to hook the wires up to a 12v supply and hoohed a gauge to the pump on the work bench and wa la, instant 60psi! NOW WHAT!!? how do i test the pressure switch cause the fuse is good
 
#60 ·
I should've posted. I tried inflating from the valve without removing the compressor. It doesn't work. There must be a valve the only allows air out and not in.

I removed the compressor yesterday and installed the three way valve. I paid $7 for it from a local supplier. It to me an hour and a half to do. It works great and will keep me on the road while I save my pennies for a new compressor.

Thanks, Doug
 
#62 ·
Compressor does not run

Before I give up on the compressor and bypass it with the $5 fix I thought I'd ask if anyone knows what could be the problem with my 2002 Bravada suspension compressor. It does not run and therer is no indicator light when you try to switch it on in the cargo bay. I checked the fuse (ECAS) and even replaced it with another 10 AMP but it did nothing. I noticed a RIDE fuse (30 AMP) but cannot find if this is for the compressor. What do I check and how do I check it? My compressor was not making alot of noise at all when running like so many others. I had that problem 3 years ago and replaced the valve which was pretty easy and the compressor worked great, until now where it does not even try to run. What gives? I may be getting the Y 5/32"OD splitter very, very soon.
 
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