Idle Stabilizer Control Unit Alternative

[zoti]

Testing the prototype.

[Abscate]

[zoti]

Today we tested the LEDs on the unit.

You can assign the LEDs to display any input or output from the unit (for instance, display RPM, Valve output, TPS etc) or error codes.


Link


This is the user interface for controlling the LEDs.

[zoti]

Next week we are going to start testing the prototype unit in my van.

I have an 88 manual with now AC but with power steering.

If you have an automatic with power steering and AC that is running in the Dallas area, we would like to test the unit on your van.

86-91 2.1L

[zoti]

Today we finally got the units in the van to start testing and configuring them.

They are working and we can update parameters and the software that runs them. Obviously, they need adjustment and that's what we are doing in the next few days.

[Aryana]

Awesome!

[zoti]

We made really nice progress today.

In the video we have one of our prototype units connected to the van and we control it from our computer.

What we are trying to do is get it to hold the idle at 875RPM and stable. It sounds easy but the engine requires constant little adjustments and things change with temperature etc.

Now that we have control and had a few boards tested we decided to make some changes to the board to make it better and easier to connect to. This will also add to the "tinkering" ability the end user will be able to do.


Link

[zoti]

We continued work on the project today setting up our test equipment and specifically, our "recorder" which will record the behavior of the original idle control unit so we can mimic it.

In the picture below you can see how operating the Power Steering creates a "blip" in the amount the idle control valve is open.

The other picture is our test and recorder rig.

[Dave Wood]

I just stumbled across the thread since I'm currently having issues. I'm in for one when it does get to production
_________________
Dave
87 Vanagon GL

[zoti]

We made some great progress this week.

We used out custom "recorder" to record the inputs and output from the original VW unit so we can analyze what it is doing in all kind of stages of operation.

We got our unit working pretty stable.

With the help of forum member DigiMatrix we got some info on how the unit behaves at different temperatures and we implemented that into our prototype.
This is beneficial for engine warmup. When you start the engine and it is cold, it keeps the idle higher to help warm up the engine and as the engine warms up, idle slowly drops to the pre set idle of 870RPM.

To do that we "faked" a temp signal and we could play with it and see how the unit reacts.

We also identified some changes that will need to be made to the printed board. For instance, out USB connector had an issue where you couldn't get the cable to fit all the way once the board was in the protective box so we are making some changes.

We are also implementing a "test" feature which will let the end user test their Idle Control Valve to make sure it is working well throughout the range of motion and is not sticking.

We made many other small changes and I hope that by the end of next week we will have several prototypes that can be tested. I plan to drive my van daily and have a unit installed so I can monitor and identify issues.

[zoti]

We made more progress today driving the van around observing the behavior of our idle stabilizer control unit. It runs the van nice and smooth and compensates for loads such as power steering and radiator fan kicking on.

We also tested our Idle Control Valve "test and clean" feature which will help you test your valve to see if it is sticking and clean it in case it does.

It basically opens and closes the valve so you can spray some throttle body cleaner in there and clean from all the crap that gets sucked into it.

[zoti]

Here's something a little more interesting than just text.

We tested the operation of the 3 LED that are on the unit. These can be set to display various inputs such as TPS, AC, PS, Transmission or RPM.

In this test we have all 3 LEDs displaying the RPM. As the engine revs the LED will flash faster.

This is great when you are trying to figure out if you have the right signals going into the unit. If you are not sure you just set the LED to the desired input and operate that input.


Link

[zoti]

Our software is almost complete and ready to go out to some beta testing.

If you are interested in testing please drop me a PM or comment here.

We are looking for people who have an 86-91 vanagon with original 2.1L Digifant engine and that have power steering, functioning AC and either manual or automatic transmission.

Here's a screen grab of the user interface.

On the left from top to bottom is the RPM display as a graph, the idle control valve percentage and engine coolant temp.

On the right is the main video displaying all the info such as numerical RPM and all the inputs.

The unit will try to maintain the RPM at the set idle (in our case we decided on 880RPM but you can change it within a range) and it will always adjust to it, measuring and correcting.

When there is a "big" demand such as putting the automatic transmission in gear, turning on the AC or using the power steering, the control unit will open the valve in much more to counter the load.

I'm working in a video showing how this happens with PS demand.

We also have a window that can show the mA demand of the valve but we are not sure if it is required at all.

[zoti]

Here are a couple of videos showing how the software is working.


Link



Link

[zoti]

We have been quiet for a bit but I'm happy to say that we have a couple of units out now for beta testing and we will have a couple more ready for some more beta testing.

I am looking for someone who is willing to help in the Dallas area who has an 86-91 Vanagon preferably with automatic transmission and AC working and who is willing to let me come over and test a unit on their van.

I have been running a unit on my van but mine is manual and only has power steering.

If you are interested please PM me.

In the mean time, I have a little bit of info to share with those of you who are trying to understand and diagnose the idea control system in the vanagon.

This is the Digifant IACU plug

If you want to test it, here's a description on how to do it.

Use a DVOM (Digital Volt Meter) to test the pins of the ICU Plug to confirm you
are getting all signals. Set your meter to DC Volts and test per the list below.
First thing to do is test your Van's battery. You may think it's good but it might not
be and a good battery is key to good operation of your electrical systems.
To test the battery place your negative lead of the meter on the negative battery
pole and positive lead on the positive pole.
A good battery should read 12.6V with the engine off.
Start your car and observe the reading. Any reading between 13.5V - 15V is
good.

Pin tests
15 & 31 should have 12V (battery voltage) when turning the key to the run
position. Note that vans 86-89 get this power from the fuel pump relay so you will
have power for 2-3 seconds when you turn the key to run or constant power when the van is running. 90-91 vans get power from the DigiFant relay so they
will have power all the time once the key is in the run position.
T & 31 should have 0-5V. The hotter the engine, the higher the voltage however
if you have 0 then it is disconnected and if you have 5V then there is a short.
1 & 31 should show in the range of 6V with the engine running. This is the RPM
signal coming from the hall sensor and 6V is the average voltage.
LH & 31 will show 12V (battery voltage) when the steering is turned all the way to
the lock position and held there.
Any other time it should be close to 0V.
LS & 31 will show 5V when the throttle position is in the closed or fully open
throttle and 0v in any other position.
50 & 31 will show 12V (battery voltage) when the automatic transmission is in D
or R and when the starter is engaged. Any other time it should be close to 0V.
K & 31 will show 12V when the AC clutch is engaged.
Any other time it should be close to 0V.

[ALIKA T3]

Thank you for the test procedure
_________________
Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[75Flamebug]

Thanks for the testing pin outs! Do you think you’ll sell this unit when it’s complete? It’s looking pretty awesome! I’d help but I’m not in Dallas and don’t have AC or power steering.
_________________
1975 (Standard) Flame Bug
YouTube - KlutchKyle
Instagram - 75FlameBeetle
----------Since Oct 2014----------

[bobhill8]

That is great info all organized in one place. Into the files it goes. Thank you.
_________________
1986 Westy
1971 Squareback

[Garth1980]

Great information.
Thanks

[zoti]

We are working on some new prototypes that will now have USB-C connectors for reliability and durability.

We need a few more beta testers. If you are interested, please read the requirements below and PM me.

To be a beta tester you need:

- A 86-91 Vanagon with the original Digifant system in good working condition.
- You should have the power steering and AC in working order.
- Manual or Automatic (we prefer automatic).

- A PC Laptop to run our software that connects to the Idle Control Unit with a USB Cable.
- Basic understanding of the system and the time to run the tests.

The system is a stand alone system and does not need a PC to run. The PC is used to adjust parameters on the system such as basic idle, how much compensation is required when there is load on the engine at idle and it will also give you information about your Digifant system and if it is all connected correctly.