D2 Rear Air Suspension Still Dropping PLEASE HELP The sage continues. latest info

Hi All,
I am still having trouble with our 2001 Discovery 2 TD5’s rear air suspension. So any advice would be welcome.

It used to drop after about two weeks of no use, but now getting more frequent. Drivers side dropping more than the passenger side.

Read the forums and everything pointed to the air springs, even though no leaks could be found.

New air springs fitted (ouch!) Replaced compressor and solenoid valves but once to correct height, drops within hours, , 50 mm in four hours at which point the passenger side settles, but drivers side continues to drop another 20mm or so over nine hours.

This is with or without compressor or vavles electricallly connected, Tried to get to ride height then isolate air springs supply, but still the same, although not sure how successful isolating was.

just as it did just prior the changing the springs. This happens in O/R mode as well.

Compressor inflates almost straight away, no signs of a leaks anywhere.

Where should I be looking now?

The battery had gone flat sometime ago, could the load sensors lose their position?

Is there a procedure for disconnecting them to clean contacts up?

Will they find their position if I inflate system, disconnect battery, unplug sensors, re-connect battery then plug in sensors.

I know there will be those of you out there saying go to coils, but.

You wouldn’t buy a Breitling watch, then check the time on your mobile.

Any Ideas?

Many thanks

Mike

elmscroft said:

Hi All,
I am still having trouble with our 2001 Discovery 2 TD5’s rear air suspension. So any advice would be welcome.

It used to drop after about two weeks of no use, but now getting more frequent. Drivers side dropping more than the passenger side.

Read the forums and everything pointed to the air springs, even though no leaks could be found.

New air springs fitted (ouch!) Replaced compressor and solenoid valves but once to correct height, drops within hours, , 50 mm in four hours at which point the passenger side settles, but drivers side continues to drop another 20mm or so over nine hours.

This is with or without compressor or vavles electricallly connected, Tried to get to ride height then isolate air springs supply, but still the same, although not sure how successful isolating was.

just as it did just prior the changing the springs. This happens in O/R mode as well.

Compressor inflates almost straight away, no signs of a leaks anywhere.

Where should I be looking now?

The battery had gone flat sometime ago, could the load sensors lose their position?

Is there a procedure for disconnecting them to clean contacts up?

Will they find their position if I inflate system, disconnect battery, unplug sensors, re-connect battery then plug in sensors.

I know there will be those of you out there saying go to coils, but.

You wouldn’t buy a Breitling watch, then check the time on your mobile.

Any Ideas?

Many thanks

Mike

Click to expand...

Hello Mike, can I just summarise, you have replaced:

Both air springs;

The compressor and it's associated valves.

Ok well really the only components left are the ride height sensors.

If you disconnect the neg lead on the battery before disconnecting them, then swap them side to side, then reconnect them and afterward reconnect the battery - that should show if it's the sensors that are the problem.

I'm assuming you do all this testing with the doors closed and the engine running?

Ride height sensors cost about £30 apice and normally you would replace both at the same time.

Also normally, if you have disconnected the battery neg lead the slabs ECU should retain the height setting - the only problem might be that your battery went flat so I'm not sure what effect that might have had.

Worst case scenario is you'll need to find someone local with a Nanocom to re-set the height.

Good luck, keep the air springs as they give a nicer ride than steel springs,

Dave

The other thing would be the airhoses between compressor and springs.. i can't see why ride height sensors would cause a slow drop myself.

Try disconnecting the battery when it is up and see if it still drops. If so it must be a leak therefore the pipes would be the next logical suspects.

David

Hi Dave
Thanks for the quick reply.

The measurement were taken, once Discovery reached normal ride height, about 60mm bump stop tip to axle. Then switched off and height monitored.

It raises and lowers when off-road mode is selected, so one would assume sensors are ok, but I will do as you suggest, to tick another box.

I am leaning towards the idea of it losing its position, via the flat battery,
although I haven't found this fault on the forum.

Trouble is it can go weeks with not being used, not good I know.

It is starting to do my crust a bit and hurt the bank balance, but I will keep going and hopfully it will help someone in the future.

Just read your post and new pipe is on order.

Will keep all posted,

Thanks

Mike

Hi All,

Still at it

Well, renewed pipe, still no difference.

When I'd jacked back to to replace pipes and run engine up, suspension levelled out, then dropped weight off jack fully down, suspension dropped another 20-30mm, but immediatly rose, suggesting load sensors are ok.

Looks as though diagnostics is calling.

Anyone close to Swindon? or what do I buy?

Thanks Again

Mike

elmscroft said:

Hi All,
Replaced compressor and solenoid valves but once to correct height, Any Ideas?

Many thanks

Mike

Click to expand...

are u speking about the exhaust valve(nr 9) and the pressure limiting(nr 6) valve too??.......(as numbered in RAVE air supply unit description)

Anyway to isolate these u have to clog somehow the supply/exhaust of the system(nr13).........dont give up yet it cant be so mysterious.

mine had to be recalibrated with textbook after i had new compressor fitted.For no reason it kept dropping down on to it's bump stops overnight.After recalibration it was fine

Mine dropped when I sat in the boot for an hour with engine off. Just offside rear, where I had been sat. Was proper worried for a while, but seems ok silly question, but have you got a lot of weight in the rear?

elmscroft said:

Anyone close to Swindon? or what do I buy?

Thanks Again

Mike

Click to expand...

I have Nanocom in SP5, willing to help if you can drive here.
Mark

Hi

Thanks guys, and Mark for the offer, I will see what happens when a guy comes over with a genral scanner.

Everything seems to work fine and as it should with the engine running, but drops when the ignition is off.

Keep you all posted.

Thanks for the advice

I suggested before, and I can't see if you said you have tried but the easy to guarantee whether it is a leak or the system venting air intentionally(but wrongly) is to disconnect the battery and see if it still drops. If so definitely a leak.

David

Mike,

it may no help much, but since few months ago I had the same problem (also falling from the right side, which in my case happens to be the side of the rear fuel filter, but not the driver seat. Mine is LHD). Does it help knowing that LHD and RHD vehicles have very similar problems??? I have a 2001 TD5 with air suspension and ACS.

I got the connector that goes into the fuel filter changed, and in only drops in 10% of the cases it did before. That is, using it daily, stopping the car 3 or 4 times x day minimum... now it drops "only" once a week (before it was dropping a dramatic 50% of the times I would stop the car) . It is a big change, but not a perfect solution that has worked for about 2 months of daily use. It must have anything to do with that change.

My mechanic told me it must be an electronic issue, not anything else. He will have a look at it soon.
It only drops when the engine does not run (many times just just a minute after)

I tended not to believe what he says, but the fact that he changed that single plug, toghether with the filter tells me that I should consider this option... luckily the told me not to change anything after checkig the air suspension with a spray...

I will let you know when and how I completely solve this... if I-he can.

I like to think that we have a much reliable air suspension system than P38 Range Rovers, wich has been recognized officially by LR as a black-sheep in the family in this aspect. Apparently when they analyzed RR P38 reliability they improved the system before handing it over to the Discovery II Series. But still, when you suffer it, your are puzzled by its apparent lack of logic or lack of ability to diagnose which is the problem by everyone ...

bluesticky1...you sat in the boot for an hour? My local garage sells sacks of spuds for a fiver

SOLVED, Faulty new air spring.

Thanks for everyones help and support.

Mike

Hi,
I'm looking for a little help on this topic.
My disco has been squatting for a while now. Goes up fine when started, but sits overnight etc.
I replaced both air bags yesterday, but it was down this morning.
after replacing the air bags I noticed that there was a noise from the compressor area when the car was turned off, so after finding this thread I followed the advice given by David Pye ie disconnected the battery, this resulted in the noise from the compressor stopping.

I therefore assume that the fault is electrical rather than a leak (wasted £150 on air bags!!). Does anyone have an idea what could be the problem?

Thanks

Chris