Excellent description, this should help a whole lot, Thanks! Before i actually do this job a couple more questions. The front bags lose air while driving but when I let them inflate after i park it they stay full for days. More than once after parking the car i actually see the car drop rapidly and hear the air rushing out of the bags. I fire the car back up the bags fill and no more leak. It's all very (seemingly) random.
The first time I caught this it was the front driver side only but now it has rapidly progressed to both front bags. What does this mean. It sure appears to me to be a solenoid that's on the way out. Could this be a problem @ the compressor/dryer?
Yes, I have thoroughly scanned the forums but I personally haven't arrived at a conclusion that satisfies me. Figured I'd start with the solenoids. Any Thoughts?
You've accurately described my previous condition. The leak seemed totally random. While my leak was in the left front air spring only, the front of the car dropped. The passenger side would end up only slightly (one inch?) higher.
Since the system is active for an hour after the ignition is off, and the car sometimes (but not always) dropped after parking, the electrical system/controller was suspect.
After messing with it over the years, it got bad. The "check suspension" lamp lit about 3 times while driving and the suspension dropped. I pulled over. The compressor was very hot to the touch. It had been working VERY hard.
So, I finally decided to fix it and went through the entire system, including the self-test sequences (again). I swapped a few parts, including the one driverside solenoid.. but no joy. (To test a solenoid just pull it's color-coded line from the dryer. Air either will or won't slowly exhaust from that line. The only other place a solenoid can leak is from it's little o-rings inside it's mounting boss on the spring.)
Anyway, I could not find the sequence of events to make it fall on command, ie turn off ignition / open door, get out / shut door.. listen to it pump up and then wait for it to deflate.. it was a real brain teaser.
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My problem was a simple leaking 'bag'. The rubber is thin.. a one-ply fabric with a rubber coating. Let me talk about these things for a moment and share the mental picture..
First off, the rubber must flex into a 180 degree U-shape at the bottom during use. The flexing stretches the rubber's outside surface. Ozone attacks the rubber and causes those tiny cracks, like in a old tire sidewall that's been attacked by ultraviolet and ozone.
The cracks extend all the way through, but they don't always allow air through. The cracked areas, which are usually on the exposed tire-side of the spring, must be under a particular degree of stress to open the cracks.
Sometimes the cracks are slightly above or below (inside) the U-shaped bottom curve. The car does not settle to precisely the same height every time it's parked,
so the spring doesn't always leak down.
Anyway, i was down there the otherday, spraying soapy water as i had done many times before, when i saw for the FIRST TIME small bubbles all around that outboard side of the lower part of the bag.. and i was happy. My suspension was 99% fixed in my mind.
A trip to the junkyard.. an '89 LSC with springs that were still full of air and hard after a maybe a year of sitting in the weather.. and the rubber was smooth, black and clean. They cost me $40 each for the fronts... not a great deal but who cared at that point.. not me.
If i have any worries it's the compressor which was over-taxed for a month or so, overheated and seemingly frozen the piston. I used a wet rag to cool it off on the side of the road for about 5 minutes. It then pumped as normal.
But thus far, the problem is gone and it's as if it never existed. The car actually steered a lot better.. Encouraged, I have since installed new struts and shocks.. parts about $200 there plus some sweat. Thursday is new mufflers for about $150..
ok.. try this. Get it pumped up and spray soapy water on the spring. Use good lighting and watch closely as it deflates. Having someone sit on the fender might provoke it to deflate.
I hope you have my luck and see the leak(s).
