Tool for adjusting AHC torsion bar

[eleblanc]

Not being able to read pressure from the ODB connector. I decided to make myself a tool to test pressure.

I made myself 2 gauge, but one would do.

sometimes, for unknown reason the AHC wouldn't lift up to HIGH all the time. I suspected my TB weren't adjusted properly

IMO any shop playing with AHC should have this.

Took the bleeder and welded a standard fitting on it.

A hose and a 0-1000psi gauge

And the result both sides before i cranked the TB.

Left side
http://www.ericleblanc.com/gallery/...2_GALLERYSID=1f218c23849a7667514d2b1017ce2645

Right side
http://www.ericleblanc.com/gallery/...2_GALLERYSID=1f218c23849a7667514d2b1017ce2645


I then adjusted the left to 900 and right to 800 and now the truck goes to high without problems.

 

[uHu]

I then adjusted the left to 900 and right to 800 and now the truck goes to high without problems.

As long as the wheels are straight, the left and right are connected, so you should have the same pressure on both sides. L-R TB adjustments are used only to level the truck laterally. Normally you just crank both the same number of turns.
How come you got differing readings?

 

[eleblanc]

There is a 100# difference.... I don't know why, can't remember is the fuel tank more to one side?

 

[uHu]

There is a 100# difference.... I don't know why, can't remember is the fuel tank more to one side?

If you cranked a TB between the two readings, you would get a difference.
Which side of the car is heavier doesn't matter if the pipe across is open - you measure at two ends of the same open pipe.
Different adjustment of the two TBs compensates for uneven weight distribution.

Looking at the T0yota LSPV gauge, I notice that the bleeder-plug attachment has the hole straight through, instead of on the side as on a normal bleeder.
Also, the kit has a bleeder-plug next to the gauge. Don't know if that matters though.

 

[eleblanc]

I see what you are saying, the valve should be opened between each side therefore each reading should be the same. Do you know which connector should I read on the pressure switch? I'll try to compare.

Visually the left side tb is alot more cranked then the right side.

Unless somehow the shock or tb was damaged when the hdj rolled. The left side wheel was hit right on and the wheel camber was totally wacked out. We keep everything else from the uzj

If you cranked a TB between the two readings, you would get a difference.
Which side of the car is heavier doesn't matter if the pipe across is open - you measure at two ends of the same open pipe.
Different adjustment of the two TBs compensates for uneven weight distribution.

Looking at the T0yota LSPV gauge, I notice that the bleeder-plug attachment has the hole straight through, instead of on the side as on a normal bleeder.

 

[eleblanc]

Also I made sure to cycle the truck height before checking the other side.
The Toyota tool is probaly better because when I unscrew the bleeder to check pressure it leak a bit....

 

[uHu]

Do you know which connector should I read on the pressure switch? I'll try to compare.

???

Visually the left side tb is alot more cranked then the right side.

The left is normally more cranked, as the tank and the (heavy) driver are both on the left. (btw, on 80s (w 4 x coils) you can see they develop a lean to the left after a few years)
The visual is not much to go by though, as you also have the splines. So if you run out threads on a TB, you take it off and move the splines a notch or two.

 

[eleblanc]

The connector on the accumulator valve as a plug, I believe 5 wires, do you know which is for pressure. I could compare resistance.

 

[lexi4darin]

Aside from home made tools by folks that can weld, what do the rest of us layman do to get pressure readings?

I need to get my readings done on the 18th of Feb but I don't have the LSPV tool? And on a serious note, does anyone offer an app for that? An OBDII read out app that scans/understands the AHC codes? I got an iphone that can work with the OBDII but I don't know which, if any, provide LSPV or pressure readings.

 

[eleblanc]

I think only dealer can read the AHC ecu.

 

[Kenso]

There is some software on ebay that claims to duplicate the functions of the dealership diagnostic tool. Whether it actually does or not I can't say. Comes with the software on a cd to be installed on a laptop and a communication cable to connect between the obd2 port and the laptop. About $150 if anyone wants to take the plunge and risk it. I'm going to eventually try it in a few months I think.

 

[eleblanc]

My truck is from europe and there the standard was MODB, OBDII in europe and in diesel only became standard around 2004 i beleive.

I have the dealer software and can connect to the truck diagnostic, but AHC does not work. that is why i used the gauge.

 

[lexi4darin]

How can I check the pressure manually with gauge similar to the above custom welded device?

And I'm no welder.

 

[uHu]

The connector on the accumulator valve as a plug, I believe 5 wires, do you know which is for pressure. I could compare resistance.

The 5-pin plug on the accumulator, or on the actuator in fact, does not have a pressure signal. The actuator (that the accumulator/gas-spring is attached to) only has 4 valves which give the 16 steps of damping.

The valve body located inside the frame-rail has 4 additional valves, two leveling valves (1 front, 1 rear) which open when a height adjustment is required; and 2 gate valves which close between left and right in curves.

The AHC system measures the pressure only at the pump, and takes a reading when a leveling valve is open in order to determine the hydro/gas pressure at each axle.

 

[uHu]

How can I check the pressure manually with gauge similar to the above custom welded device?
And I'm no welder.

Go to a hydraulics/hosemaking shop and get the required parts put together.

Might be a challenge to find the 7 mm bleed-plug-hole adaptor. One option could be to get an M7 bolt, cut it and chamfer it, and drill a hole through it. But then to find a hydraulic fitting for that 7mm could be just as hard. Brings us back to welding
When t0yota has found an M7 adaptor, it must be poss to source it somewhere.

Some pix:
1 is the LSPV gauge adaptor for ahc bleeder together with the bleeder plug.
2 is the list of adaptors of the LSPV gauge kit.
3 is the three straight adaptors, qty 2 each.

 

[RoderickGI]

How can I check the pressure manually with gauge similar to the above custom welded device?

And I'm no welder.

I just found this thread. For others with the above question, since I've answered lexi4darin in a PM previously, I bought a Waekon ABS and Brake Pressure Testing Master Kit to do my setup.

It is available from lots of stores, but I found The Tool Warehouse was the cheapest when I bought. It is a lot cheaper than the Lexus tool, or other aftermarket toolsets, and appears to be identical except for the labeling and logo on the included paper manual.

I tried to get the parts in Australia to make up my own gauges, because it should be easy, right? Wrong. No-one had the correct fittings, let alone a bleed nipple next to the gauge, and most weren't interested in a one off build.

Eleblanc you should really be using a 3000 psi gauge. While static loads probably won't exceed 1000 psi, I saw dynamic loads up to 1500 psi when I did a short "settling in" test drive with the gauges attached. Just a thought to take note of.