Rear suspension collapsed - No air pressure

[DruLS]

Hi everyone, 

Some bad news I'm afraid. While taking a drive today I noticed the ride quality suddenly became very stiff and bouncy. Imagine super cheap coilovers. I was bouncing around in my seat so I knew something wasn't right. I pulled into my destination and saw that the rear end on both sides it very low. Almost as if the struts are not holding air at all. The fronts appear to be fine. At first I was worried that the struts may have gone bad. However this happened on both sides at the same time, and the car only has 100k on it which seems low for a strut failure. Here's a picture to give you an idea of what it looks like:

As you can see the rear end is completely bottomed out. No warning lights came on. I also did a full scan with TechSteam and saw no codes relating to suspension. Do any of you have any idea of where I can start looking? I'm hoping it's just something simple like a failed air line. Does anybody know if both rear struts are fed by one line? That would explain the issue I guess. 

I'm going to get it up in the air soon to see if I can see anything wrong but I've never worked on the suspension on one of these. If anybody can provide any tips or if you have an idea of what may have caused this I'd really appreciate your input. 

Many thanks

[Jake430]

Sorry to say 2 new structs, air bags are blown. each corner feed by its own air line and solinoid

[DruLS]

1 minute ago, Jake430 said:

Sorry to say 2 new structs, air bags are blown. each corner feed by its own air line and solinoid

Just what I need. Wouldn't it be unusual for both to fail at the same time though?

I did post this on a FB group and I'm having a mix of people telling me it's the struts and others saying it could be a height sensor. 

[Jake430]

I  am 99% sure. make sure the compressor is not left running or you will need to replace it too. You should be able feel the rip in the bags. Sorry to say they are not the best Considering  what they cost.

[messi]

Sounds like air bags, very expensive, unless you buy second hand, but then how long will the second hand ones last. I'd get it converted to coilovers. 

Also if you haven't done so already, replace the radiator too, they are prone to leaking coolant into the gearbox causing gearbox failure, your car has hit 100000 miles, best to replace it to be on the safe side

[The-Acre]

Listening for the compressor constantly running will give you a clue as to whether the strut is leaking. I doubt both have gone at the same time though. A height sensor failing can cause it to bottom like that, you need to get it up in the air to check it out.  The sensors can be taken apart, cleaned and refitted if you're careful.  Remember the struts have an outer rubber cover, this cover has a split in it from new so that's not an indication of the air bag having blown. 

Should you need to replace them don't be put off by horror stories of how difficult it is, it isn't.  I replaced all four on mine with new Arnott struts from the US, total with shipping 2.4k!

 

[DruLS]

1 hour ago, The-Acre said:

Listening for the compressor constantly running will give you a clue as to whether the strut is leaking. I doubt both have gone at the same time though. A height sensor failing can cause it to bottom like that, you need to get it up in the air to check it out.  The sensors can be taken apart, cleaned and refitted if you're careful.  Remember the struts have an outer rubber cover, this cover has a split in it from new so that's not an indication of the air bag having blown. 

Should you need to replace them don't be put off by horror stories of how difficult it is, it isn't.  I replaced all four on mine with new Arnott struts from the US, total with shipping 2.4k!

 

Those are the ones from Rock Auto right? How are you finding them? I'm not too worried about replacing struts. Never worked on air suspension but replaced shock/springs many times. 

A lot of people on LS430 FB groups seem to think it's a broken sensor anyway so let's hope it's that. 

[The-Acre]

1 hour ago, DruLS said:

Those are the ones from Rock Auto right? How are you finding them? I'm not too worried about replacing struts. Never worked on air suspension but replaced shock/springs many times. 

A lot of people on LS430 FB groups seem to think it's a broken sensor anyway so let's hope it's that. 

Yes, Rockauto.  Actually I think replacing air shocks is easier, or at least as easy as changing conventional ones.  They seem fine anyway. Keep us posted.

[DruLS]

9 minutes ago, The-Acre said:

Yes, Rockauto.  Actually I think replacing air shocks is easier, or at least as easy as changing conventional ones.  They seem fine anyway. Keep us posted.

Going to get it up in the air today and see if I can figure out what's wrong with it. 

[PCM]

Odd that they both went at the same time - IF... they did.

Had a Soarer back in the day. Back end down. Was the compressor.

Good luck.

[DruLS]

1 minute ago, PCM said:

Odd that they both went at the same time - IF... they did.

Had a Soarer back in the day. Back end down. Was the compressor.

Good luck.

I thought that but if it was the compressor wouldn't the front end have dropped as well?

[The-Acre]

20 minutes ago, DruLS said:

I thought that but if it was the compressor wouldn't the front end have dropped as well?

I can't see how a failed compressor would cause the car to drop.

[RgrWynne]

Have a word with Paul Frost, not a lot he doesn’t know, plus has replacement parts. 07590 072646. Good luck, my you do get all the bad luck 🤦‍♂️

[steve2006]

Not too long ago after returning from holiday I discovered my Celsior was sitting on the arches at the hotel where it had been stood for 2 weeks. I also assumed that both rear springs had broken but after further examination by the AA it was just one side. I think what happens is the remaining spring ( in your case air strut ) ends up taking the whole of the weight of the car so compresses fully under the additional load. Once the broken spring was replaced the ride height on both sides returned to normal although I did replace both.

I’m hoping from a cost perspective this is the same scenario on your car but given the reliability of air struts it may be a wise move to replace both eventually even if only one has failed.

Another thing that was done to prevent the car bottoming out completely was the AA guy fitted some plastic spacers around the damper piston on both sides effectively lifting the rear suspension up and clear of the arches but this cannot be done on air struts due to design.

I see you got a flatbed, mine was reversed towed 20 miles mostly along the M1.

[RgrWynne]

16 minutes ago, steve2006 said:

Not too long ago after returning from holiday I discovered my Celsior was sitting on the arches at the hotel where it had been stood for 2 weeks. I also assumed that both rear springs had broken but after further examination by the AA it was just one side. I think what happens is the remaining spring ( in your case air strut ) ends up taking the whole of the weight of the car so compresses fully under the additional load. Once the broken spring was replaced the ride height on both sides returned to normal although I did replace both.

I’m hoping from a cost perspective this is the same scenario on your car but given the reliability of air struts it may be a wise move to replace both eventually even if only one has failed.

Another thing that was done to prevent the car bottoming out completely was the AA guy fitted some plastic spacers around the damper piston on both sides effectively lifting the rear suspension up and clear of the arches but this cannot be done on air struts due to design.

I see you got a flatbed, mine was reversed towed 20 miles mostly along the M1.

 

[RgrWynne]

A rare sight indeed 

[steve2006]

2 minutes ago, RgrWynne said:

A rare sight indeed 

Do you mean my other half on the left of the picture supervising the operation.....no that’s perfectly normal 😀

[bobjol]

I had exact same problem about 18 months ago.   My problem was that one of the " Rear link height control sensors"  had corroded and became detached.

My mechanic did some temporary welding repairs, but advised replacement of both units.  Car returned to normal height after start up.

Very difficult to source new units in UK, at the time.  Had to get them from US.  Cant remember total cost, but it was less than £100 including postage. Both were very easy to replace, with no major suspension work required.

[Neil E]

Yes as Bob and Phil say, it's more likely to be one of the rear height controllers or a fault / leak around the rear control valve. 

 

Credit to the guys on clublexus

 

Try this link too.

https://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/785827-help-air-suspension-issue-rear-end-bottomed-out.html

[DruLS]

Sounds like good news, if it is indeed that. I'm a bit busy today, and it's kind of cold. But it's much warmer later in the week so I'll get it up in the air and see what I can see. 

[RgrWynne]

13 minutes ago, steve2006 said:

Do you mean my other half on the left of the picture supervising the operation.....no that’s perfectly normal 😀

Actually I did notice somebody watching, but thought they too were aghast to see a Lexus being towed by a breakdown truck. I’ll bet the AA man was surprised as there are certain makes of cars they rarely attend, Honda, Suzuki, Toyota, Lexus etc. etc. noticeably all Japanese, to name but a few, and apologies for any not listed. However this is all the more remarkable when you consider how many old cars are still on the road, and probably not properly maintained. They obviously must fail at some point, but I guess the parts are designed to show failure wear, but have the ability to continue to perform. Having always been used to new cars, it is something I have had to learn, that hopefully, my Lexus will give me notice, and so I can replace or repair rather than a catastrophic failure, breakdown and all that follows. 
My brother recently had to write off his wife’s 2010 Golf Bluemotion 1.6 TDI, with 80k on the clock, which had been in the family from new and correctly serviced. The reason.... failed oil pump, which was a known fault ..... apparently. The cost to repair was not worth it, so he bought a new Honda Jazz. 

[RgrWynne]

7 minutes ago, Neil E said:

Yes as Bob and Phil say, it's more likely to be one of the rear height controllers or a fault / leak around the rear control valve. 

 

Credit to the guys on clublexus

 

Try this link too.

https://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/785827-help-air-suspension-issue-rear-end-bottomed-out.html

That is so helpful and interesting thank you , Roger 

[Malc]

8 minutes ago, RgrWynne said:

so he bought a new Honda Jazz.

all singing all dancing then 

Malc

sorry, too much jollity here I guess

[Neil E]

Just checked eBay and as mentioned earlier by Roger, Paul Frost is a good source for supplies and instruction.  He stocks controllers second hand if that is the issue. 

Hope that's the fault, as they are quick and easy to replace.

[RgrWynne]

1 hour ago, Malc said:

sorry, too much jollity here I guess

Sometimes it is nice to have joility, sometimes it is too serious.......methinks