Yes, good plan. Except that the accumulator check wont be worth much until you have the pressures and heights right.Alright, got through all 30 pages. I have a much better understanding of the system but I could still use some advice with my truck. I picked up a 2003 LX with 148k miles. It has been in southeast Virginia its whole life and has very little rust. The AHC will go to L and N without an issue. When I select H it will blink a few times and then N will be lit solid. When the truck is in N the center cap to fender height is 21" all around. I got techstream working earlier and my pressures are all too high. My understanding of what I need to do is as follows:
Does my plan sound reasonable?
- Check the accumulators by measuring the change in fluid level when going from L to N.
- Flush the system with new suspension fluid.
- Adjust height sensors to bring the front down to 19.75".
- Crank on the torsion bars to get the pressures down and reindex the torsion bars as necessary.
- Order either King or OEM + 30mm spacers for the rear.
Would the pressures being off or sensors being maladjusted prevent it from getting into H?
Why does the passenger side height sensor seem to lag so much?
Nice. Which vendor did you buy from? AISIN is clearly visible on my sensor so I would not mind picking up a passenger side one from them. I have never purchased from Partssouq before but they have the lowest price ($182.57) I have seen for the OEM units.Well, it finally happened.... '98 LX and first AHC issue after 21 years, 176k miles. While on a 2500 mile roadtrip, the AHC "off" light would blink occasionally and then one day, the front end dropped down to near the bumpstops. Pulled over, trying H-N-L modes and fiddling with the height sensors.... figuring there might be a dead spot around the "N" height of the sensor. After 10 minutes, the ride height went to normal! I was able to drive home 1000 miles with the AHC "Off" light blinking much of the time.
While home, ran the diagnostic codes... and Front, DS, height control sensor was showing error. I removed the sensor and opened it up to clean the contacts and spring but was not able to fix it. Internals didn't look too bad, except the corrosion or residue on one of the springs:
Ordered up both L & R front AHC sensors from two different vendors.
Aisin HST-020 ($100)
These are the OE parts for less than 1/2 the price if from Toyota. The actual sensor a la carte can be had for $25 from aftermarket vendors but I wanted OE and besides, my linkage/heim joints were looking kinda tired.
In the meantime, I disconnected the Front DS sensor and actually drove it around town for about 10 miles. The AHC "Off" light blinked the entire time but the vehicle height stayed normal! I thought this was interesting. So, if your front end drops, can you just disconnect the bad sensor and keep going on your merry way?
Today, I replaced both front sensor and all is normal, no error codes!
View attachment 2018163
Update to my risky decision installing 80 series Dobinson springs in the back (standard height spring) on sensor lifted LX470. Driven 10k miles now.
The springs have taken a good amount of driving to settle and get to the same comfort levels that I am used to having. After a 300lb combined weight of of a Dissent rear bumper and spare tire, I still have amazing comfort with full AHC capabilities. Took a pressure reading and was excited to see how capable this setup can be in the future. 06 LX has nearly 200k miles, rear shocks replaced at 150k, all Globes and accumulator as well as front shocks are still original. 13 ticks on the graduation level.
View attachment 2018169
4.1 MPa-g! The shocks start to shut off partially at around half a tank of fuel, but the dampers continue give a good ride. Once filled up there is no problem. Its ready to take anything I throw in it!
I have a lil thread on this fyi PLEASE HELP AHC pogo stickYep. Are all of your AHC components stock?
I replied to that threadI have a lil thread on this fyi PLEASE HELP AHC pogo stick
My globes are palides with about 2k miles on em and my rear springs have about 4k miles, my fluid is a wonderful clear red coming from all 5 bleeders and before this problem started everything was working perfectly with good heights level pressures ect graduation test is 14 and in H mode it works flawlessly
The problem with these sensors is the seal, or rather how the flat lid can't stand the pressure of the seal. The lid bends a bit between the screws, so that the seal gets too little pressure to keep humidity out. One way of sealing it better is to put a 5-6 mm aluminium plate on the outside of the lid, with 5 mm longer screws. The seal then makes a perfect fit all the way.....I disassembled the old sensor out of curiosity and was surprised at how clean it looked compared to others I have seen on the site. Upon closer inspection the middle spring looks like it is bent/shorter than the others and has some dirt/corrosion on the base of it. I am surprised it was enough of a problem to cause an issue though.
I came looking for answers to a similar question, so maybe the answer to mine can help both of us. I had everything balanced L-R via TBs before I started adjusting height sensors. I had trouble getting the sensor to move within the adjustment slot, so I turned this nut thinking it would help:
- How do I get the two sensors closer to agreeing with each other?
- Shorten the passenger side sensor until it reads closer to the driver side and then remove preload on the passenger side torsion bar?
- Extend both sensors further and then increase the preload on the driver side torsion bar?