Monday, February 20, 2006 - 05:35 pm, by: Rohan Muller(Bcnr33gtr)
Hi All,
My 91 UZZ31's airbags seem to sag right down on the back only overnight. But this doesn't happen every night. Also, while i'm driving, especially after i just pull up, i hear the compressor firing up quite regularly.
Having never owned 1 of these before and using the VERY helpful search function, before posting, i still have no idea. Do I need to replace the rear airbags??? Any simple tests I can perform???
Monday, February 20, 2006 - 06:46 pm, by: Mark Paddick(Sparks)
or maybe the solenoid valves, easy to pull apart and clean. Check if both sides go down by the same amount, if so I would hesitate to blame BOTH airbags. Could even be intermittent fault in the control computer, they are full of cracked and dry joints after 15 years.
At the age of these cars now new airbags is not a bad idea. I can certainly vouch for the improved ride and handling. Cost is not THAT bad if you say it quickly
Don Bagnall Moderator New Zealand I have LESS Soarers than Hayden :-(
Monday, February 20, 2006 - 07:27 pm, by: Mark Paddick(Sparks)
I can point you in the direction of a couple of old bags....They both hate me but they may take a shine to you, especially if the bottle isn't empty yet
Don Bagnall Moderator New Zealand I have LESS Soarers than Hayden :-(
Monday, February 20, 2006 - 09:41 pm, by: Rohan Muller(Bcnr33gtr)
Mark, 1 side does sit higher than the other all the time (drivers side) but it seems to go down fairly evenly. Are the valves linked in any way? Where are the solenoids located exactly? Would an uneven height confuse the control computer, therefore letting it down? Recently had a full front and rear alignment, but the problem was happening before as well. It can also drop right down in a matter of about 3 hours. I left it for 8 hours today, and it hasn't moved. What would be the cost to get the 2 bags replaced? And not with the 1's you were offering???
Monday, February 20, 2006 - 10:39 pm, by: Andrew Meiers(Acmtt)
I have two for sale for $100 each. But check that its not the problem Mark is talking about. New price is approx $700 each. Apparently they are better than the originals, although that is very hard to quantify.
Monday, February 20, 2006 - 11:01 pm, by: Mark Paddick(Sparks)
AAAAwww, but one of them's in Toowoomba, no freight or travelling time (that's why I left!!!)
$770 each last I checked.
I bet left front is down most of the time? the rear adjusts as a pair they are not independant like the front so if one side is consistently up at the rear the other side will be down at the front. Adjust the front to get it right. I have also seen some dodgy height sensors lately. They can have a number of faults. I will do a diagnostic write up in the next few day as i can't be stuffed just right now. Time for bed.
Tuesday, February 21, 2006 - 09:59 am, by: Rohan Muller(Bcnr33gtr)
Yes. Front left is the lowest. I checked the height of each guard last night over a few hours and the rear right was first to go down. Rear left did go down, but not all the way like it normally does. Fronts go down about 1.5" on right and 3/4" on left.
Mark, did your bags go down at all the way over night???
I'll have a go at correcting the height of the fronts to match. Should i do that with weight in the drivers seat or just let the control computer work that out?
If its still playing up, I'll then check out the height modules (when you get around to writing up a diag for us).
Then if that doesn't fix it, it looks like I'll need to replace at least 1 bag. Andrew, where in Vic are you?
Tuesday, February 21, 2006 - 10:28 am, by: Mark Paddick(Sparks)
One would go down without warning, any time any place. I was living in Toowoomba then too, you may have seen it.
It sounds like right rear may be leaking. If the sensors are working properly with/without driver won't matter. Do you have the wiring diagram CD? They are relatively cheap and a good investment, even if you can't read them yourself they are handy to have if you need electrical work done. Most auto electricians won't have them. Available from Jeff Harper. If you have the diags you can verify that the height sensor outputs do actually vary with the height of the car, I've seen some that don't, they just stay at the normal output volts (around 2.5V). If this IS the case then the height of the car will not be controlled by the computer and will vary with whatever pressure happens to be in the struts at the time.
Rohan Muller Tinkerer Victoria V8 UZZ31, R33 GTR V-Spec
Monday, February 27, 2006 - 12:44 pm, by: Rohan Muller(Bcnr33gtr)
-= UPDATE =- Ok. Now i have re-adjusted the front height so both sides are the same when on level ground. (lowered front at same time. Adjusted rear height. Rear right adjustment took alot more turns than rear left to get same ride height. After driving, all sits at right height. As soon as i start up the car again, the pump starts and rear right goes higher than left. (suspect sensor and leaking air bag)
Another problem i have now is, after 2 medium speed right hand corners, the front left airbag has almost fully deflated and tyre touches guard. Then it pumps up again when stationary. Is this the sign of another faulty airbag, or is this normal Soarer behaviour???
Monday, February 27, 2006 - 01:41 pm, by: Mark Paddick(Sparks)
You CANNOT adjust the rear height independently of each other in the airbag cars. They pump up and down together. I have never really worked out how the rear sensors interract but the control system is only 3 channels, Front R, Front L and rear so rear can only be adjusted together. Uneven rear height is therefore either faulty rear struts or more often the opposite side front strut low/high (opposite to what rear is doing).
Check the solenoid valves for the front, maybe one leaking. They are easy to pull apart and clean. That or the height sensor. Do the tests in the airbag diagnostic pdf. Front solenoids are in front of the compressor. Rears are in the boot, either side of the fuel tank. There is also a diagnostic connector in the boot (LH rear), you can connect switches to operate the system manually to check pump and solenoid operation.
Tuesday, February 28, 2006 - 09:54 pm, by: Mark Paddick(Sparks)
Well I would, no telling who's been caning a TT It's so easy to do!!! Unless you get one direct from Japan. They seem to be kinder to them. Judging by the number of posts along the lines of "urgent: stock turbo in good nick needed ASAP" I'd reckon that that's a fair statement
Mind you I have put new airbags in the V8 and have good working spares of all the other bits. If I had a TT you can be damn sure I'd buy the first set of known good cheap seconhand turbos I came across but then I'm like that. If I had a Pov-pack Baggmobile I'd probably buy another whole car. They're so cheap lately.
Previous
, I'd be factoring in the cost of 4 x NEW (as opposed to old baggs) for the complete....Soarer experience! 
(that's why I left!!!) 
It's so easy to do!!! Unless you get one direct from Japan. They seem to be kinder to them. 
