OMFBest89

So I just bought a 1993 LS400, fully optioned to the till.
Everything about the car is absolutely perfect, but the air suspension.
It works when the height is set to high, about 80 percent of the time. Other than that, the back sinks low, and its bouncy as all hell.
Sometimes taking it on the freeway will reset it, it levels out, and rides wonderfully. Then it gets in a mood and doesn't cooperate. Right now, I have the height control set to high, and the front wheels have gone up a little bit, but the back is still sinking.
I've checked the fuses, and they seem to be okay. Am I right in thinking it could be a relay?

timmy0tool

iTrader: (7)

due to the age of the air suspension, the air bags themselves or other components may have developed a leak. since replacement parts are very expensive (over $1000 each corner) most owners just remove the air suspension all together and opt for conventional spring/strut.

a set of springs and top hats can be located at your local junkyard or wrecker for fairly cheap. combined with a good set of brand new shocks, you will have solid suspension once again! good luck.

OMFBest89

It stays up usually when the height is working. So there are no leaks in the shocks.
and it stays level at speed, it'll just sink when parked, and sometimes it wont go back up.

sha4000

iTrader: (1)

What he said. Think about it.

RA40

iTrader: (6)

Welcome to Club Lexus and congrats on the LS.

The compressor is constantly feeding air to the leaking strut/s to keep them at height. On a properly working system, the ride height will not change when parked. The costly fix is replacing the air system, the least costly is a spring conversion as timmy0tool mentions.

j2b4o

When mine started to leak it was odd. It would stay up for weeks and than I would come out of a store and the rear was dumped. Happened a few times and I went over everything like 3 times and found no leaks. Finally I decided to jack each wheel up individually allowing the suspension to travel through the full range of motion. That is when I found my passenger rear bag had a leak that was only exposed if the shock was compressed just right. I would bet at least one your bags are leaking.

CompStruts

If you have any issues with your Struts just replace them with a new set that is not Air Suspension. Buy the Complete Conversion Kit from www.completestruts.com. Mention this post and get 10% off your order..... http://www.completestruts.com

Kingsoup

I had the same problem when my 93 air bags went, one corner started to droop and would re-inflate when fired up.
I bet you got a deal on it, now you know why!