Suspension raising times

[LRD414]

Suspension raising times. Mine takes 8s for access to normal and 17s for normal to offroad. Both take around 5s to lower. No faults or issues, just wondering if normal to offroad is a bit ‘slow’ to raise. Interested to hear what others times are & what’s normal. It’s close to 10years and 200k (2014 with AMK)

[BradC]

Did you let the system charge up and sit idle between each test? If for example you went Access->Normal, the system is going to need to run a while to re-charge the reservoir. If you went Normal->Offroad in that time then you're going to be waiting longer than if you did it with a full and idle system.

For giggles I'll time mine today.

[Eric SDV6SE]

Seems ok Scott, may still be worth checking the dessicant and valve blocks. I remember my D4 2011 typically took <10seconds between stages, e.g access to normal 10sec, normal to offroad 10sec. From offroad to access would be longer than 10sec, limited by the size of the vent valve. If from access to offroad, I recall no more than 15-20seconds, engine running in all scenarios.

[LRD414]

Did you let the system charge up and sit idle between each test? If for example you went Access->Normal, the system is going to need to run a while to re-charge the reservoir. If you went Normal->Offroad in that time then you're going to be waiting longer than if you did it with a full and idle system.
Good point and now you mention it, I'm not sure. My testing protocol needs more rigor, I'll have to re-test :)


or giggles I'll time mine today.
Would be good to have a few examples I think

[BradC]

Good point and now you mention it, I'm not sure. My testing protocol needs more rigor, I'll have to re-test :)

I know I'm being picky but when you're talking timing this stuff matters.

Normal -> Access : 6s
Access -> Normal : 4.5s
Normal -> Offroad : 4s
Offroad -> Access : 7.5s
Access -> Offroad : 22s.

Access -> Offroad ran out of puff after the rear was at height (9s) and the compressor had to run for 13 seconds to get the front to height.

Between each test the system was allowed to recharge the reservoir and stop the compressor.

Now, because I had 7 elements on the iiD (Exhaust Valve, Gallery Pressure, Reservoir Valve, Front Left+Right valves and Rear Left+Right valves) the update time and therefore my timing resolution is indicated on the graphs as 0.5s, but I expect it's closer to +/- 1s.

[Eric SDV6SE]

Brad,

Did you factor in air temperature? Humidity? Dew point and condition of the system? New desicant or 50000km of road dust? New compressor or old ? AMK or Hitachi?

[BradC]

Given we were measuring time, I ignored pretty much all of the above and simply "measured" rather than "felt". As long as the reservoir was full, compressor was off (not being so hot it tripped out) I called it good.
Having said that, I'm happy to challenge anyone to account for the extra variables listed and have it make more than a +/- 1s difference. :tease:

[Eric SDV6SE]

Given we were measuring time, I ignored pretty much all of the above and simply "measured" rather than "felt". As long as the reservoir was full, compressor was off (not being so hot it tripped out) I called it good.
Having said that, I'm happy to challenge anyone to account for the extra variables listed and have it make more than a +/- 1s difference. :tease:

Was only stirring, seems fish are biting....

[BradC]

Was only stirring, seems fish are biting....

I know, but biting is what makes it fun! Otherwise it'd just go through to the keeper.

[Narangga]

Suspension raising times. Mine takes 8s for access to normal and 17s for normal to offroad. Both take around 5s to lower. No faults or issues, just wondering if normal to offroad is a bit ‘slow’ to raise. Interested to hear what others times are & what’s normal. It’s close to 10years and 200k (2014 with AMK)

My vehicle had an AMK when I bought it in Sept 2015. The unit was serviced mid-2019 prior to a trip to the Pilbara. Indy reported desiccant was dry and no white dust/powder.

Checked my times today Scott and they were:

access to normal: 6-7 seconds
normal to off-road: 11 - 12 seconds
lowering: 6 seconds for each

FWIW.

[Tombie]

I know I'm being picky but when you're talking timing this stuff matters.

Normal -> Access : 6s
Access -> Normal : 4.5s
Normal -> Offroad : 4s
Offroad -> Access : 7.5s
Access -> Offroad : 22s.

Access -> Offroad ran out of puff after the rear was at height (9s) and the compressor had to run for 13 seconds to get the front to height.

Between each test the system was allowed to recharge the reservoir and stop the compressor.

Now, because I had 7 elements on the iiD (Exhaust Valve, Gallery Pressure, Reservoir Valve, Front Left+Right valves and Rear Left+Right valves) the update time and therefore my timing resolution is indicated on the graphs as 0.5s, but I expect it's closer to +/- 1s.

Nice work...

Quiet day at the office? [bigwhistle]

[BradC]

Nice work...

Quiet day at the office? [bigwhistle]

I was on a run to pickup takeaway for dinner. Just enabled logging on the iID and went at it. By the time I got back into the driveway all tests were complete and I could come inside and view the logs.

[MadJax]

So I have had 'Normal Height' only come up a few times recently.

Have just got hold of a Gap tool and checked a few live values.

The gallery pressure starts dropping as soon as the engine is switched off.

Is this normal?

[Eric SDV6SE]

So I have had 'Normal Height' only come up a few times recently.

Have just got hold of a Gap tool and checked a few live values.

The gallery pressure starts dropping as soon as the engine is switched off.

Is this normal?

No, you have a leak somewhere, known culprits are the airbags themselves, the central and corner valve blocks. Others leak points are the compressor cap or the supply lines to each corner.

[loanrangie]

No, you have a leak somewhere, known culprits are the airbags themselves, the central and corner valve blocks. Others leak points are the compressor cap or the supply lines to each corner.

Gallery vents as soon as you switch off so i'd say its normal ?

[Eric SDV6SE]

Apologies, I read it as the car drops as soon as switched off, that'll teach me for reading and responding on a crowded train....

[BradC]

So I have had 'Normal Height' only come up a few times recently.

Have just got hold of a Gap tool and checked a few live values.

The gallery pressure starts dropping as soon as the engine is switched off.

Is this normal?

No it's not. Provided you have > 2006 compressor software, when running the car will level and once it's level it vents the gallery. When the gallery is idle, it vents to between 2 & 5 bar (mine stops at ~2.6 bar usually). It should not drop from there whether the car is running or not. The fart when you shut it down is the suspension re-leveling once all the people get out of the car. The gallery will still have between 2 & 5 bar (absolute not gauge)

If you are seeing a steady drop in pressure then you have a leak. Compressor is the most likely culprit, but could also be a hose, fitting or valve block.

[MadJax]

Suspension has been in high for a week without the engine being started. Will rebuild the compressor tomorrow and see what happens

[BradC]

As Eric said, look for cracks between the 2 ports on the dryer cap.

[Eric SDV6SE]

Suspension has been in high for a week without the engine being started. Will rebuild the compressor tomorrow and see what happens

Did the car lower at all whilst switched off? If it hasn't, then all is normal. A rebuild is good preventative maintenance. The desicant dust travels and blocks up the valve blocks at each corner.