Air Suspension Hissing - Please direct to correct thread

[shawnwilkins]

I have a 2004 H2 Victory Edition and have a love/hate relationship. At this point, gas is the cheapest thing about the vehicle. As with everyone else it seems, my air supsension only leaks sometimes and then all the time.

When I shut off the vehicle and get out I can hear the air coming out of the suspension like if you poked a hole in a tire. It is very loud and will leak all the way out sometimes and then others only for a second.

I have read that it might be the exhaust valve on the drivers rear behind the gas cap but it seems that I can hear it on both sides. Maybe it is just because it is so loud.

Thanks and I appreciate any help. At this point I am ready to fix the truck and sell it. It has already cost me about $4000 in repairs this year and only has 80,000 miles on it.

Shawn

[PaHumBug]

Wow, $4K in repairs in... 4 days into the year :giggling:
Put coils in and keep it!

[Hellz]

so what are you askinn for here?

you selling the truck or looking to solve the problem?

for the problem..

the hardest part is going to be to try to locate the leak.
start it up and let the bags fill
(make sure it is in park with parking brake on)
go to the back and get underneath and listen for the leak.
you could also do the soapy spray bottle method and spray down all the lines.
if it is bubbling, then there is a leak.

If your compressor is contstantly running, it is only a matter of time before it burns itself out and that will add another $900 to the repair list.

so would be better to find the leak asap

[shawnwilkins]

I am not going to sell it if I don't have too....but.

Since the truck sits level for a few days and then can leak out at any moment I assumed it was not the air bags as the loud hissing noise of air coming out would point to a large hole in the bag or bags and would happen every time.

Other than jacking it up and spraying the bags, how do you check the rest of the unit.

Thanks,

Shawn

[Hellz]

spray every line with soapy water to find the leak, or pay someone to do it.

if you can actually hear the air leak, then it is a major leak that you shouldnt have problems finding.

its the slow quiet ones that will give you problems. these will be the ones you find by spraying the lines and watching for bubbles

[vandy0090]

is the truck leaning when u come out to it after its sat for a while? if so your in luck. its just an air bag. while it sounds like a crappy thing its really one of the cheapest and easiest things you will fix on the damn thing. go to gmpartsdirect.com find the rear air sping and order 2 of them. i made the mistake of doing mine one at a time. my first went out at about 40k and the other one went about 2 months ago at 70k. they are about 90 bucks a piece.

its easy as hell to fix. jack up the truck and let the rear axel hang. put some jack stand on the frame. i used a knife and just cut holes in the bags. reach up on top and there is a small plastic tab. push it down and twist the bag clock wise if i recall corectly. twist it about an 1/16th of a turn. and it will drop down. the line is a quick disconnect. push it in to the bag. hold the little ring down and the line will pop off. install the new air line click it in to place then jack the rear axel to seat the bag on the hat. once its seated start the truck up. it will blow up and lift off the jack stands. lower the jack and ur good. there are some good vids on youtube about how to do it. it look me about 15 min my first time.


good luck with the damn thing. i feel your pain though:lame:

[shawnwilkins]

Thanks Vandy,

Unfortunately it is the whole rear end that drops and just one side. This is what leads me to believe it might not be the air bags but both of them could be leaking.

Hopefully this weekend I can jack it up and take a look and maybe it will just be an exhaust valve or even a loose fitting. The fact that it does not leak all the time and for some days not at all and then every day at times, maybe it is something that is getting jarred around when driving.

Thanks again!

Shawn

[vandy0090]

thats how mine was. some times it would be both flat. some times just the pass side. it would go a month with no issue then everyday for a week it would go flat. it was dry rotting out where it curls under. ez way to see it it hit the ride level button that will jack the rear a couple inches and you will see where its rotting out.

good luck sir

[shawnwilkins]

ok, I finally had a chance to look at the Hummer this weekend and rasied the rear bags as high as I could with the additional ride height. I sprayed both bags with a mixture of soap and water and did see a few very tiny bubbles but nothing that causes the hissing noise after parking the vehicle. Once I lowered the bags to normal ride height they did not show any signs of leaking. Obviously they need to be replaced but they are not my leaking issue.

I am going to assume that it is the valve behind the gas cap area that is sticking open for some reason at different times. Can anyone direct me to a thread or video of what I am looking for. I have the Victory Red edition that has the chrome gas cover and would like to know how to remove it and then what I am looking for once I do.

Thanks,

Shawn

[Easy Ed]

On my 2003 there was a "filter" on the drivers side, maybe you are hearing air trying to enter it ? Really wouldn't think you would when the truck/compressor is not running though ?

It was rusted pretty bad causing poor air intake to the compressor making it work harder and it then cause the compressor to shut down till the next time I started the truck.

There is a picture of it here http://www.elcovaforums.com/forums/showthread.php?t=24471 scroll down to post #12 to view it.

Ed

[shawnwilkins]

ok, I probably need to check that as well.

I guess what I need to know is where is the exhaust valve located. I am pretty sure that is what is getting stuck and leaking air. Any photos would be appreciated as well.

Thanks,

Shawn

[Easy Ed]

2003 single stage compressor info from 2003 service manual.

Ed

http://i639.photobucket.com/albums/uu112/esheri/HUMMER%20H2/IMG_0231.jpg

[shawnwilkins]

Easy Ed....thanks for the diagram. I got up under the vehicle last night for just a minute while I could hear the air coming out and it did appear to be coming from the compressor unit area.

Thanks again.

Shawn