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Mysterious P.S.I drop

 
Old 09-08-16, 12:08 AM
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vipXjunky
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Default Mysterious P.S.I drop

Hey guys,

I have a problem, maybe someone can help me out? I searched countlessly for answers, but I can't seem to find the answer.

Air sus. details:
Air force struts and bags.
Air force box management with viair compressor.
SMC check valves
Wedge type fittings

My situation:
When I air up to my drive height, which is usually about 2 finger gap between fenders and tires, my PSI will hold over night without any issues.

That being said, when I try to roll at a LOWER P.S.I. (no finger gaps) my rears would gradually drop little by little and eventually drop to where im tucking my rims. I checked all air lines and fittings, there is absolutly no air leaks.

My question is, how is it that my air holds over night at drive height, but dumps within 30minutes of driving at a lower PSI?? Are my struts blown? Is there another way air can leak besides fittings?

Thanks in advance for any help!
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Old 09-14-16, 01:11 AM
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ultm8mind
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Manual or auto controls? If it's auto it may be trying to compensate for something whether it be pressure or height.
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Old 09-15-16, 12:58 AM
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sojah
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i had a very similar problem and had to order a new SMC CHECK VALVE from bagriders.com for like 20$ and it fixed the problem.

my shop here was able to figure out it was the check valve by listening to it with a stethoscope and you could hear a faint sound of air leaking with it.

i was very skeptical at first but after the 20$ valve was replaced the issue was fixed, soooooooo....
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Old 09-21-16, 01:47 PM
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Originally Posted by sojah View Post
i had a very similar problem and had to order a new SMC CHECK VALVE from bagriders.com for like 20$ and it fixed the problem.

my shop here was able to figure out it was the check valve by listening to it with a stethoscope and you could hear a faint sound of air leaking with it.

i was very skeptical at first but after the 20$ valve was replaced the issue was fixed, soooooooo....
I got the problem fixed, it was the check valve as you mentioned. The reason why it only dropped PSI during a low ride height was because the back pressure was stronger vs. drive height, the back pressure is a lot less because there was more air in the bags. Not sure if that made sense.

Thanks again to those that inputted their opinions! you guys are the real M.V.P.
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