PADDO, From reading the FSM and reading posts it is also my conclusion that the height control accumulator does not affect ride damping, but just need others options as well because I am running out of patience and $. My neutral pressures have been checked first by a gauge set I had made and screwed into the bleeder plug, then by using the techstream software on my XP laptop. I made a slight adjustment to the tortion bars last year and replaced the rear springs. The settings are right on now. I replaced the globes with aftermarket ones originally. When the ride went hard, the vendor sent me a second pair for free with the toyota OEM spec pressure. The second pair with a little less pressure rode the same. Now I have OEM toyota and the ride is once again the same - so blaming the globes seems out of the question since this is my 3rd attempt. I pulled the power to the vehicle several times, once to change the battery and notice no change. When I got the LX the front shocks were leaking so I changed them and of course learned how to bleed everything. I changed the plastic AHC fluid reservoir because it was so dirty I could not see the fluid level. Using a dip stick the old globes were at about 9 and the new right above 14 notches. After changing the reservoir I still notices small black particles in the fluid. I removed, cleaned and replaced it, still have dirt showing up. Then my rear shocks began to leak, so I replaced them and once again cleaned the reservoir flushed with 2 cans of fluid and now my fluid seems to stay clean. I am thinking the shock seals were throwing off small black sealant into the AHC fluid and it was making it up to the plastic reservoir and sticking to the side walls. The heat almost performed a chemical like bond and i could not scrape it off the inside of the old reservoir. So now I have really fresh fluid, 4 new globes and 4 new shocks no codes and a stiff ride and the comfort selector barely works. I took it to the Lexus dealer and they cycled system up and down probably 10 times in a row and got a code. C1762 fluid pressure malfunction(pump and motor does not supply fluid). The first level tech called me said I needed a new pump assembly, something about $2000. I said no, I have an issue with the ride quality not height. Then they handed me off to a very nice diagnostics specialist. He said I do not need a pump(yes they would have been happy to take my $ for nothing). The code is generating because the height accumulator is stuck and does not move. Apparently it is an 800 psi charged piston which the pump fills with fluid and then can be released quickly to control the height. When it freezes the symptom is when going from L or N to H(lifting the vehicle) with the selector switch the pump comes on immediately and pumps up the vehicle. With a properly functioning accumulator the vehicle raises quickly with the stored pressure and the pump can fill the accumulator later. My LX has done this since I have had it for 2 years - I just did not know my accumulator was bad. Eventually the pump will give out working too hard. So, does the accumulator have anything at all to do with ride quality - I share your opinion that it does not, but I would like to be really sure since it is getting expensive to start replacing parts. So what parts are suspect? Damping force actuators are the only thing remaining if that big height control accumulator is not on the list of suspicious parts. When I bought the vehicle, the first time I bled/flushed the fluid a lot a air came out followed by real ugly fluid. The LX was a one owner serviced at dealer always. I pulled the records, they show motor oil changes along with many very picky issues but not one mention about AHC fluid -91k miles and 9 years. If the fluid was never changed would the damping force actuators fail gradually from heat/lack of lubrication excessive air? I am waiting for the tech to perform every diagnostic check on the system and tell me what part has failed. I will post the results of this no matter what the outcome. This forum has helped my greatly, thank you for posting your thoughts.
