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Old Jan 10, 2014 | 01:47 PM
  #1  
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Default Air issue continue

Setup, 5 gal tank, twin 380cs, vu4 manifold, dakota digital management. 3/8 line, d2 racing double bellow bags all 4 corners. 120/150 switch.
ride height is at 80 front 65 rear.
the issue is when airing up. I have 3 settings, full dump (bags at 16 psi), ride height, and full height.

when from full dump going to ride, if i press the preset, it attempts to hit the target psi, will usually get there, but the car is still way too low. have to bring bags to almost 100, then lower it back down to ride height.
And if i go from ride height to full height, well it wont reach it, controller will time out sometimes.
if i try to go full height from dump-forget it, wont reach it.

From dump to ride when i hit the auto height button, the pressure will drop below 120 and compressors will come on. If i want to get to ride height quickly form dump, i have to raise front first, then rear.


Sorry for the haggered sentences, bear with me.
WHat are your guys thoughts?

i also thought a higher tank pressure would help. afterall its a fairly small tank for 4 double bellows and 3/8 line.
so i installed a 150 off 200 on. that didnt work, at all. 215 psi not off, down to 0 psi not on. old swithc works fine. Whatever, faulty switch. Problem is the vu4 dindt like it too much, would not pump one corner, or fail to air up at all. Even when I did try to get the front all the way up, it still woudlnt when holding the button down. I would have to release teh valve. and then try again to get it a little bit higher. I know the car car lift high enough to easily stick your fist in the wheel gap, because Ive done it. It just wont do it from the get go..


another thing to add, is my pressure sensors for each corner are liek 5" away from the manifold. A total of maybe 1.5 feet worth of tubing from the tank. Tank pressure reads 150, but when i hold teh valves open for the front, the pressure will only reach to like 112 forexample, while tank pressure has dropped to 130. I would understand this different reading if the pressure sensor was on the bag 15 feet away, but this is a foot away!
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Old Jan 10, 2014 | 10:10 PM
  #2  
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Default

Originally Posted by Greg5OH
Setup, 5 gal tank, twin 380cs, vu4 manifold, dakota digital management. 3/8 line, d2 racing double bellow bags all 4 corners. 120/150 switch.
ride height is at 80 front 65 rear.
the issue is when airing up. I have 3 settings, full dump (bags at 16 psi), ride height, and full height.

when from full dump going to ride, if i press the preset, it attempts to hit the target psi, will usually get there, but the car is still way too low. have to bring bags to almost 100, then lower it back down to ride height.
And if i go from ride height to full height, well it wont reach it, controller will time out sometimes.
if i try to go full height from dump-forget it, wont reach it.

From dump to ride when i hit the auto height button, the pressure will drop below 120 and compressors will come on. If i want to get to ride height quickly form dump, i have to raise front first, then rear.


Sorry for the haggered sentences, bear with me.
WHat are your guys thoughts?

i also thought a higher tank pressure would help. afterall its a fairly small tank for 4 double bellows and 3/8 line.
so i installed a 150 off 200 on. that didnt work, at all. 215 psi not off, down to 0 psi not on. old swithc works fine. Whatever, faulty switch. Problem is the vu4 dindt like it too much, would not pump one corner, or fail to air up at all. Even when I did try to get the front all the way up, it still woudlnt when holding the button down. I would have to release teh valve. and then try again to get it a little bit higher. I know the car car lift high enough to easily stick your fist in the wheel gap, because Ive done it. It just wont do it from the get go..


another thing to add, is my pressure sensors for each corner are liek 5" away from the manifold. A total of maybe 1.5 feet worth of tubing from the tank. Tank pressure reads 150, but when i hold teh valves open for the front, the pressure will only reach to like 112 forexample, while tank pressure has dropped to 130. I would understand this different reading if the pressure sensor was on the bag 15 feet away, but this is a foot away!

Are you running paddle switches or AVS switch box?
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Old Jan 11, 2014 | 12:16 PM
  #3  
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dakota digital management handles the up down.
wondering if maybe i have to recalibrate it or something. Ive had the battery disconnected a bunch of times but that didnt do anything.
Going to measure voltage at the pressure sensors this week.
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Old Jan 11, 2014 | 09:48 PM
  #4  
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get rid of those gauges and just the elevel and be done with it

Last edited by swtjlsy; Jan 12, 2014 at 08:32 AM.
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Old Jan 12, 2014 | 11:44 PM
  #5  
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really dont want to throw a 400$ part at something without knowing the root cause.

checked voltage at tank pressure sensor, car on, it was reading 1.57 v?
also wheni checked the pressure rigth at the vu4 manifold with my digtal tire pressure gauge it read 133 while tank pressure was reading at 150 on the dakota gauge.
Either my gauge is wrong or the sensor is sending false into to the dakota brain.

Last edited by Greg5OH; Jan 13, 2014 at 12:05 AM.
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Old Jan 14, 2014 | 10:17 AM
  #6  
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Default

Originally Posted by Greg5OH
Setup, 5 gal tank, twin 380cs, vu4 manifold, dakota digital management. 3/8 line, d2 racing double bellow bags all 4 corners. 120/150 switch.
ride height is at 80 front 65 rear.
the issue is when airing up. I have 3 settings, full dump (bags at 16 psi), ride height, and full height.

when from full dump going to ride, if i press the preset, it attempts to hit the target psi, will usually get there, but the car is still way too low. have to bring bags to almost 100, then lower it back down to ride height.
And if i go from ride height to full height, well it wont reach it, controller will time out sometimes.
if i try to go full height from dump-forget it, wont reach it.

From dump to ride when i hit the auto height button, the pressure will drop below 120 and compressors will come on. If i want to get to ride height quickly form dump, i have to raise front first, then rear.


Sorry for the haggered sentences, bear with me.
WHat are your guys thoughts?

i also thought a higher tank pressure would help. afterall its a fairly small tank for 4 double bellows and 3/8 line.
so i installed a 150 off 200 on. that didnt work, at all. 215 psi not off, down to 0 psi not on. old swithc works fine. Whatever, faulty switch. Problem is the vu4 dindt like it too much, would not pump one corner, or fail to air up at all. Even when I did try to get the front all the way up, it still woudlnt when holding the button down. I would have to release teh valve. and then try again to get it a little bit higher. I know the car car lift high enough to easily stick your fist in the wheel gap, because Ive done it. It just wont do it from the get go..


another thing to add, is my pressure sensors for each corner are liek 5" away from the manifold. A total of maybe 1.5 feet worth of tubing from the tank. Tank pressure reads 150, but when i hold teh valves open for the front, the pressure will only reach to like 112 forexample, while tank pressure has dropped to 130. I would understand this different reading if the pressure sensor was on the bag 15 feet away, but this is a foot away!
The sensors are suppose to be tapped in to the back of the VU4 valve to be accurately measure the pressures
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Old Jan 14, 2014 | 10:21 AM
  #7  
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interesting. however i dont think 4" away will account for a 20-30psi pressure drop. hmm,
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Old Jan 14, 2014 | 07:15 PM
  #8  
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I have to be honest with you gauges are just a fancy toy. They let you see pressure reading and that's all each corner is never the same. if you install the system correctly you should have no leaks. Elevel is the next step up to gauges, if you are worried about ride quality them you need to tune your suspension. Once you do that it will ride great.
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Old Jan 15, 2014 | 02:22 AM
  #9  
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I had the same problem when I had air suspension. The only difference is that I didnt have any memory on the guage, just pressure numbers. And yes, from dumped I had to raise the car a bit higher than drive height, and then lower it a little bit. That way the guage and ride height were ok. But If I raise the car only to the ride height psi, the car would still be too low.
eLevel is the thing I would put now, but I´m on coils now.
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Old Jan 15, 2014 | 08:44 PM
  #10  
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i think this started very recently. Are these leaking check valves? One compressor was significantly cooler than the other when i went form 0-100 psi.


will check tnak pressure tomrrow.
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Old Jan 15, 2014 | 09:00 PM
  #11  
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MDefinitly leaking, dropped 7 pai in 15 mins. no leaks at connections, just verified again.
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Old Jan 16, 2014 | 05:08 AM
  #12  
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this is driving me crazy. somehow the leak originated yestrerday or two days ago. I never had this problem before. Tank is way down this monring, still making noise that air is coming out of it, my right front bag was down 10 psi. Or so theyres a leak on the bag line, but why the hell is it bringing down the tank pressure with it?!
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Old Jan 16, 2014 | 09:35 AM
  #13  
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heres another video. leaks starts and stops by itself. da fuq
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Old Jan 16, 2014 | 09:37 AM
  #14  
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maybe there's a leak at the valves. thats the only way tank and line pressure will drop at the same time. just noticed a leak in my tank this morning. dropped 20 psi over 10hours time. had to take the truck to work to be safe
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Old Jan 16, 2014 | 09:41 AM
  #15  
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something us wrong with the vid. its not allowing me too upload it or play it. or is it my phone
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