• Hint: Use a descriptive title for your new message
    If you're looking for help and want to draw people in who can assist you, use a descriptive subject title when posting your message. In other words, "2008 LaCrosse" isn't going to indicate to anybody that you need help. However, "Need help with my 2008 LaCrosse" will. Be as descriptive as you can. Please use common sense... This message can be closed by clicking the X in the top right corner.

04 Park Avenue Ultra rear air suspension slow leak

ljinnc

Buick Newbie
9
0
0
Buick Ownership
Buick
HI, I'm new to the forum. I recently bought a 2004 Park Avenue Ultra with the rear leveling system which wasn't working when I bought the car. I was checking out and found the fuse for the compressor pulled, replaced and pump runs but not lifting car. Inspected rear shocks and they looked terrible, installed a new set of Monroe shocks, connected the air lines, reinstalled the fuse and car lifts and pump will finally shut off. System is working but seems the pump runs more than it should. But when I park the car for a couple hours or more it appears all the air has leaked out and pump runs quite awhile to raise car. I sprayed soapy water on all the lines and the fittings at the shocks but couldn't find a leak. Any ideas? Might the leak be in the compressor itself? Thanks
 

HotZ28

Full Member
7,098
345
83
Buick Ownership
1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
If you can not find leaks anywhere else, I would suspect the exhaust valve is leaking?
 

txbarney

Full Member
269
2
18
Central Texas
Buick Ownership
Buick
there is valving inside the compressor unit......HOT is saying that the valve that lets air out of the system is either bad or maybe has dirt stuck in it.
That valve is needed in a case where you load the car with people and stuff....the car levels itself.....when everything is removed air needs to be released or the rear would be very high.
 

bigsky

5.7L LT1 Member
SUPPORTING MEMBER
434
11
18
Montana
Buick Ownership
97 PA (salvage 185k), 99 PA (sold 140k-now 150k), 2K PA (sold 120k-now 170k), 03 PAU 167k, 04 PAU
I am chasing the same issue on a guess what...a 2004 PAU. With my symptoms, I'm thinking it might be the level sensor. Sometimes 5 seconds after I turn the key, the compressor starts running (the delay is supposed to be 45-60 seconds). The compressor will run briefly, then a minute later will fill briefly again, and then later, say after a half hour of driving will fill for a good ten seconds. BTW, the shocks are new Monroe (the old were leaking badly).

Adding to that, after parking the car, a minute later there will be a gigantic exhaust of air, like the system has overfilled itself. I picked up a used sensor but have not put it in yet.

----------------------------------------
The service manual lists other areas (besides the tubes & shock fittings) to check with soap bubbles:

-Solenoid Valve (replace compressor head if leaking)...I think this is the one HotZ28 mentioned.

-Air Dryer to Compressor head O-ring (replace air dryer if leaking).
-Air Dryer Cover (replace air dryer if leaking).

-Air compressor head gasket (replace compressor head if leaking).

-Air compressor head cover gasket (tighten bolts to 50 lb in if the gasket is leaking. If the leak persists, replace the compressor head).

-------------------------------
Short answer, yes...could be the compressor and/or the air dryer.

Has to be either: shocks, shock fittings, air lines, level sensor, air dryer, or air compressor head. THAT'S IT...(except for the wiring to and from the sensor).
______________________________
 

ljinnc

Buick Newbie
9
0
0
Buick Ownership
Buick
I am chasing the same issue on a guess what...a 2004 PAU. With my symptoms, I'm thinking it might be the level sensor. Sometimes 5 seconds after I turn the key, the compressor starts running (the delay is supposed to be 45-60 seconds). The compressor will run briefly, then a minute later will fill briefly again, and then later, say after a half hour of driving will fill for a good ten seconds. BTW, the shocks are new Monroe (the old were leaking badly).

Adding to that, after parking the car, a minute later there will be a gigantic exhaust of air, like the system has overfilled itself. I picked up a used sensor but have not put it in yet.

----------------------------------------
The service manual lists other areas (besides the tubes & shock fittings) to check with soap bubbles:

-Solenoid Valve (replace compressor head if leaking)...I think this is the one HotZ28 mentioned.

-Air Dryer to Compressor head O-ring (replace air dryer if leaking).
-Air Dryer Cover (replace air dryer if leaking).

-Air compressor head gasket (replace compressor head if leaking).

-Air compressor head cover gasket (tighten bolts to 50 lb in if the gasket is leaking. If the leak persists, replace the compressor head).

-------------------------------
Short answer, yes...could be the compressor and/or the air dryer.

Has to be either: shocks, shock fittings, air lines, level sensor, air dryer, or air compressor head. THAT'S IT...(except for the wiring to and from the sensor).
On mine when I start the car the compressor comes on in about 5 seconds, Does this short delay indicate a problem itself? I saw above the delay should be 45-60 seconds. But mine comes on and runs until the shocks fill then shuts off. I'm still not sure that it's raising to the proper ride height, does anyone know what that would be and where to measure?
 

ljinnc

Buick Newbie
9
0
0
Buick Ownership
Buick
Wow....I'm impressed too. Great information though. Thanks alot
______________________________
 

bigsky

5.7L LT1 Member
SUPPORTING MEMBER
434
11
18
Montana
Buick Ownership
97 PA (salvage 185k), 99 PA (sold 140k-now 150k), 2K PA (sold 120k-now 170k), 03 PAU 167k, 04 PAU
Does this short delay indicate a problem itself?
I'm thinking yes. I will be putting in a used level sensor next week...will report back on how it goes. None of the other PA's I have worked with had such a short delay.

For the ride height, easiest to first do the "eyeball" check. How does it look? Reference by looking at the frame rail between the front and rear wheels. The frame should be close to level. Slight variance is acceptable IMO. What I am looking for is something way out of spec.

BTW...The level sensor is easy to adjust, loosen a little bolt & adjust the arm...but just slightly either up or down depending...
 

Irish

Full Member
125
9
18
Buick Ownership
2003 Park Avenue, 2003 Buick Leabre Limited
I bought a 2003 Park Avenue last summer. The shocks worked, but it seemed like the compressor was running a lot and it was worse if there was anything in the trunk. After replacing the shocks twice, putting new air lines on it, and rebuilding the compressor I bought a pair of shocks off Amazon with coils springs on them for $107. The back end came up and stays up even with weight in the trunk and the ride is still good. I found the shocks at: http://www.amazon.com/Monroe-90007-Rear-Strut-Assembly/dp/B0047DDB70/ref=sr_1_5?ie=UTF8&qid=1459689266&sr=8-5&keywords=buick+park+avenue+shocks

When I got rid of the air shocks, I pulled the air ride relay out of the fusebox under the back seat and there was never an idiot light on the dash telling me the air ride wasn't working. I have read here that some have had a light come on after replacing the air shocks.

If you do decide to buy a new compressor to keep it stock there are aftermarket compressors available online from a company called Suncore that are much less expensive than the OEM. If I would have found these first, I probably would have kept the air ride. They are on ebay at: http://www.ebay.com/itm/1997-2005-Buick-Park-Avenue-Air-Suspension-Compressor-with-Dryer-/311411794150?fits=Make:Buick&hash=item488196e0e6:g:u40AAOSwpDdVJ9Hs&vxp=mtr
 

ljinnc

Buick Newbie
9
0
0
Buick Ownership
Buick
I bought a 2003 Park Avenue last summer. The shocks worked, but it seemed like the compressor was running a lot and it was worse if there was anything in the trunk. After replacing the shocks twice, putting new air lines on it, and rebuilding the compressor I bought a pair of shocks off Amazon with coils springs on them for $107. The back end came up and stays up even with weight in the trunk and the ride is still good. I found the shocks at: http://www.amazon.com/Monroe-90007-Rear-Strut-Assembly/dp/B0047DDB70/ref=sr_1_5?ie=UTF8&qid=1459689266&sr=8-5&keywords=buick+park+avenue+shocks

When I got rid of the air shocks, I pulled the air ride relay out of the fusebox under the back seat and there was never an idiot light on the dash telling me the air ride wasn't working. I have read here that some have had a light come on after replacing the air shocks.

If you do decide to buy a new compressor to keep it stock there are aftermarket compressors available online from a company called Suncore that are much less expensive than the OEM. If I would have found these first, I probably would have kept the air ride. They are on ebay at: http://www.ebay.com/itm/1997-2005-Buick-Park-Avenue-Air-Suspension-Compressor-with-Dryer-/311411794150?fits=Make:Buick&hash=item488196e0e6:g:u40AAOSwpDdVJ9Hs&vxp=mtr
That's some great information. I am considering just putting the Monroe airline kit AK29 on mine and eliminate the electronic system. Anyone else did this? Satisfied with the results? How much air pressure to get correct ride height and handling?
 

bigsky

5.7L LT1 Member
SUPPORTING MEMBER
434
11
18
Montana
Buick Ownership
97 PA (salvage 185k), 99 PA (sold 140k-now 150k), 2K PA (sold 120k-now 170k), 03 PAU 167k, 04 PAU
I will be putting in a used level sensor next week...will report back on how it goes. None of the other PA's I have worked with had such a short delay.
Just wanted to do the follow-up. I got the used level sensor installed, and while it works better than the original, it is still a little erratic. Most of the time the minute delay is present, but occasionally the compressor will run the check within 5 seconds. Overall, the compressor does not run as much; though I may still have a small leak.

I adjusted the sensor to allow the max height, and the height is still about a half inch lower than where the other sensor put it. The old sensor was adjusted to the middle and so could go higher or lower.

I'm going to live with it for now.
______________________________
 

84ZZ4

Full Member
201
3
0
Morrisville, NC
Buick Ownership
'83 Regal T-Type, '01 Park Avenue Ultra, '02 Park Avenue Base
For anyone else considering the aftermarket compressor, I did that on our '02, and it turned out great. It works exactly like the system was supposed to from the factory. The original compressor had a frozen closed exhaust valve, and so over time it would over-inflate the rear shocks to maximum safe capacity. It's been fine for about a year now. I bought new shocks because of the issue but it turns out there was nothing wrong with the originals so they're still on there.
 

Fred482

Full Member
SUPPORTING MEMBER
40
1
8
Western Oregon
Buick Ownership
'88 Buick Park Avenue, '94 Buick Park Avenue
I have had issues with three of these vehicles. The rear air shocks wear out and the material of the air system is no exception. Both my '88 & '94 recently had to be replaced. The earlier replacement that I performed on the '88 (that has since been sold) had over 200K on it. The current '88 had bad air boots on both shocks, cracked and well worn with 140K miles. The '94, same deal only at less mileage. The age comes into play with the air system too.

I was fortunate, by doing exhaustive searching, I was able to find factory original replacement parts for all three cars. I spent about the equivalent of the aftermarket stuff and have always tried to keep GM parts on my vehicles. The '94 was the hardest, nobody had the right ones, I tried an outside source and had to return the first pair as they were for Canadian built cars but was fortunate to talk to a rep who actually knew her stuff and found a set NOS. They were the original GM equipment parts that sold for over $500/pair, I purchased them for $160. I have had better success than some owners with OEM parts as I've heard all the stories of how "GM makes junk, it's all made in China, etc". I still like the fact that the original equipment stuff usually fits without the hassle I've had with aftermarket parts.

All three vehicles worked well after replacing the air struts, I only had to slightly adjust the ride height sensor on the '94 to make it work correctly. I have found that by adjusting the sensor to keep a very slight positive pressure in the air chamber, it keeps the boot in the correct position without the wrinkles that I've seen on some of them. Not sure it's important, but several of the ones I've taken off had wrinkles & creases in the old units and they were cracked in those creases.
 

ljinnc

Buick Newbie
9
0
0
Buick Ownership
Buick
On my 04 I finally decided to just use the Monroe air line kit AK29 and now its got standard air shocks but everything is working great and the car rides nice and smooth so with coupons I spent $58 for a set of Monroe shocks and $14 for a set of airlines and I'm happy.
 

bigsky

5.7L LT1 Member
SUPPORTING MEMBER
434
11
18
Montana
Buick Ownership
97 PA (salvage 185k), 99 PA (sold 140k-now 150k), 2K PA (sold 120k-now 170k), 03 PAU 167k, 04 PAU
On my 04 I finally decided to just use the Monroe air line kit AK29...
This is one alternative...the only thing is now it is a manual fill, but at least one has full control over the amount of air in the shocks. I carry an air tank in my trunk so that would be one way to have air available if one does not have a compressor.

...I bought a pair of shocks off Amazon with coils springs on them for $107. The back end came up and stays up even with weight in the trunk and the ride is still good.
This is a second option, eliminates the need for air, and would seem to work well if one rarely carries back seat passengers or puts heavy loads in the trunk. The worry here is some of the reviews (Amazon & Forums) mention the rear of their vehicle (not always PA's) now rides quite high, and has not settled. This will be an issue when an aftermarket shock is designed to fit a variety of vehicles.

In addition, there is a review on Amazon that states there is a new design on these, which is less prone to the noise problem some have had. I suppose the only way to know for sure if they will work is to try them out; they are really not that much money.
______________________________
 

rstairs

New member
2
0
1
Buick Ownership
2003 Buick Park avenue
I have an 03 Park avenue and I had somebody replace the air shocks in the rear of the vehicle but there was something wrong with the compressor and it wouldn't fill the shocks so the guy put a fill valve in the trunk of my car so I can fill it up manually. How much as pressure should be in the shocks, does anyone know?
 

2007LucerneCXL

Full Member
2,992
899
113
Illinois
Buick Ownership
2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
Not knowing the shocks that were installed, most will have some type of notice of maximum PSI not be exceeded, basically they would be filled so the car sits level. How much PSI is depending on level of gas in the tank and what may be loaded in the car and trunk.
 

rstairs

New member
2
0
1
Buick Ownership
2003 Buick Park avenue
Not knowing the shocks that were installed, most will have some type of notice of maximum PSI not be exceeded, basically they would be filled so the car sits level. How much PSI is depending on level of gas in the tank and what may be loaded in the car and trunk.
Yes around the fill valve it says there is a Max air pressure of 200 psi....I normally keep the gas half full and normally only two people in the front seat, maybe my daughter in the back and groceries in the trunk... I never have the car or trunk packed down...right now I have 30 lbs in there, the same as the tires, lol.
I am worried about the tires, will it wear out my tires faster if I don't have the correct amount of air in the shocks?
And thank you very much for helping me.
 
Last edited:

2007LucerneCXL

Full Member
2,992
899
113
Illinois
Buick Ownership
2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
As there's no spec on the PSI, it's a visual setting on general usage. If you wanted a mesured amount, use a tape measure behind the front tires at wheel well base and in front of the rear tire wheel well base on rocker panel. A little more accurate, but you shouldn't have a issue with tire ware and you can always look from the rear to see if the tires look square.
 
Pedal Commander
Top