Hi All

My name is Adin and I'm currently in the works of a Programmable, Easy to use, Easy to install ECU as a DIRECT PLUG IN replacement for the 5CU system used in the XJ6 Series 2 and 3

The only downside I see with making a ECU this way, we will have to sacrifice a ECU so we have the original plug... BUT if the connector on the 4CU, 5CU, 6CU, 16CU, 26CU and the 36CU are the same (the connector NOT THE PINOUT) I can fit a 5CU board in say a 26CU box... But thats only if the connector is the same

Because of interest from a certain JaguarForums member, I'm also doing research into a V12 model for the XJ12 and XJS

I have aptly named it the "L-Jetduino" because the prototype I'm creating uses the Arduino environment. The Arduino uses an 8-Bit AVR ATmega328 running at 16MHz to 20MHz

Future versions I'll program in C and probably use a 18-bit microcontroller for a bit more power and accuracy

UPDATE:

All Updates will be kept on this thread and my to do list is below

Currently focusing on the 5CU but has veered to look at the V12 ECUs (6CU,16CU,26CU,36CU) because of waiting for parts

Things to do:
Read MAP Tables from a SD card
Calculate RPM from Ignition pulse
Interface with the Temp Sensors AND Air Flow Sensor
Actively Calculate Injector Pulse Length from RPM and Sensors
Design Injector Driver Circuitry

Future Ideas:
USB interface + Windows Software
Sequential Injection Mod (without changing the harness) For Individual Injector control
Wireless Handcontroller
Custom Trip Computer (Maybe)
SD Card Data Logging
Rev Limiter (not sure how I will do this one, but I'll think about it)

If you have any ideas at all... or any features you would like your ECU to have, let me know, I will most certainly think about it and if I can incorporate it, I will

SD Card:
All settings AND MAP tables will be saved on a SD card (Up to 2GB)
Parameters needed (Bracketed is default settings pre-saved to each ECU):
* Engine Size (4.2L)
* Amount of cylinders (6)
* Injector Flow Rate (21.5lbs/h)
* "Fall Back" Air Fuel Ratio (14.7) Used when "Limp-Home" is active or the SD card isn't inserted
* Lambda Feedback Enable (True)
* Safe Min Air Fuel Ratio
* Safe Max Air Fuel Ratio
* Volumetric Efficiency - You dont need to input this, this is calculated by the program and saved to the ECU and the SD Card... Its used when "Limp-Home" is active or Lambda Feedback is Disabled

UP to 10 Individual MAP tables
Each Map can be as coarse or as accurate as you want it to be the ECU will interpolate to find missing values

Cold Start, Idle and Full Open Adjustment Tables
Using a simple + or - adjustment you vary the air fuel ratio

eg. If your at say 2000rpm and you have a 15.1:1 Air/Fuel ratio and you go to "Full Open", the full open MAP can -1.1 from the air fuel ratio to make it 14:1 (until it hits one of the safe limits)

Limp-Home Feature:
In theory, the ECU should only need a Ignition pulse input to provide the correct timing and pulse length... so if everything else fails for some reason (being Lucas it could happen), you can un-plug all the sensors (Lambda, Water Temp, Air Temp and Air Flow and the car should be able to limp home, it may not be very fast, or very powerful, but it'll get you somewhere safe so you can work on fixing it

Direct Replacement:
Being a direct replacement, My ECU will plug into your existing socket and will work straight off... if my ECU fails or requires an upgrade, you can simply insert the original ECU and it will be fine

Hand Controller:
The hand controller will consist of a 16x4 Screen (16 characters by 4 lines) Back-lit screen. It will be able to display the following
* The Cars Battery Voltage
* Injection Pulse Length
* Desired Air Fuel Ratio (From the MAP)
* Actual Air Fuel Ratio (From Lambda Sensor)
* The Value of the analog sensors (Water Temp, Air Temp, Air Flow)
* RPM of the motor
* Volumetric Effecienty
* Currently Selected MAP

The Hand Controller will also be able to change the MAP "On-The-Fly" as in while the motor is running.

 

If you have any questions or are interested, Let me know please

It would be nice to know how many people are interested

 

Not sure if anyone is following this thread or not, but I just updated my blog

When I get paid on Tuesday I'll design the circuit I have so far (on a breadboard) and see if i get a result

 

I've got the V12, but I'll be following this with interest!

 

What ECU does the XJS run? is it the 16CU or something different?

Plus.. Would you guys be interested in sequential injection if i could make it without modifying the motor itself (just as a future addition)?

 

UPDATE:

At the moment (using SMD components) the board size is no bigger than a credit card... Gotta love SMD

But that is only the Power Supply, the Lambda Amplifier and the Microcontroller... I still have to add some filter circuitry for the tach sense and work out what values the Water Temp, Air Temp and the Airflow Sensor are at for various values

 

The earlier XJS V12's had a 6cu, then a 16cu, which is considered an upgrade and will work on the 6cu motors. I'm not sure when they changed to the next upgrade, but it won't work on the older models.

 

I think the biggest problem with sequential injection would be the wiring. The injection harness is hard wired to fire 3 injectors at once. Any change would require a major wiring job from the ECU to the motor.

 

hehehe "Upgrade" its all lucas anyway, its either part working or not working at all

And true... but i think i might have a way to work on sequential without changing the harness at all.... but thats a long way in the future

I just pulled a 5CU apart and i started to work out how it worked, BUT it has 3 of these 10 pin metal can transistor looking things with a black heatsink on them... im not tempted to go any futher with them cause its a working ECU

 

What features would you like to see in a ECU?

Data Logging?
Hand Controller?
Real Time Map Changing?

Anything else you would like to see?

 

The ability to plug into a laptop and if you could control individual injectors, the ability to shut one down at a time for diagnostic troubleshooting.
Perhaps some sort of easy-adjustment to switch power-bands as well? One for fuel consumption, another for power, etc..
I just sold my spare ECU for my XJS V12, BUT I do have an 87 XJ6 parts car. I can check to see what it has in it for an ECU if you're interested.

 

The laptop will be reasonably easy, but will require more programming by me for windows (which i don't have much of)...

Individual Injectors: The 5CU fires all 6 injectors at the same time (so a sequential injection mod will have to be made to accommodate that)

I'll probably have a switch to select between 10 different maps (but you don't NEED to use all 10), or incorporate the switching into the hand controller (or even make a custom trip computer to replace the one in existing jaguars)

The MAPs (Fuel Tables or whatever you wish to call them) are saved to an SD card that you can slip into the ECU... They can be edited in excel (or any program that can save a CSV file)

CSV = Comma Separated Value

Each tables X axis is the RPM (in 500rpm steps) and Y axis is Air flow (as a percentage measured from the air flow sensor)... the data you put in is the Air/Fuel Ratio you want for a set Air Flow and RPM... Example Below (I put 14.7 in because it defaults to that if a SD card isn't detected)

100,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,1 4.7,14.7,14.7,14.7,14.7
90,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
80,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
70,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
60,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
50,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
40,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
30,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
20,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
10,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14.7,14 .7,14.7,14.7,14.7,14.7
0,500,1000,1500,2000,2500,3000,3500,4000,4500,5000 ,5500,6000,6500,7000

The calculation is based off a motor that has 100% VE (Volumetric Effecienty), so the calculation will be close to right, but no motor is 100% VE, so lambda feedback will ACTIVLY correct it (and if I put in data logging, it will calculate the VE of the motor and save it to the SD card)

Each file is saved as MAP0.CSV, MAP1.CSV.... MAP8.CSV, MAP9.CSV and a SETTINGS.CFG file to store the necessary settings (Paramaters for my calculation, If you want lambda feedback enabled or not, etc)

There will also be some other tables (1 for water temp adjustment, 1 for air temp adjustment, 1 for cold start, etc)

The Micro-controller will store the basic settings in its memory, so if you forget to re-insert the SD card, the car will still work...

I'll also program a "Limp Home" feature, where the tacho input should be the only needed input to get the right Air/Fuel ratio needed to at least drive the car home (or to somewhere you can fix it up)

I'll have the hand controller be able to change these settings on the fly (it will save the settings if you tell it to OR if the ignition is switched off)

And thanks JameyXJ6.... I have to earn some more money to continue my project any further than it has... I've just had a month off work cause of an illness I have

 

ever heard of MegaSquirt ECUs??

its all been done before! by many companys

 

Yes i have ronbros, but here in Australia, a Megasquirt or any other aftermarket ECU costs $500 or more (http://www.shiftkits.com.au/index.ph...products_id=38 as proof) and requires rather extensive programming by the user to get it right... Yes it might be more powerful and Yes it might be better, but Im looking for ease of use and installation.... My ECU is a DIRECT replacement, it requires NO extra wiring, NO changing of plugs, when you get it off me (when im finished with it) this is what you do:

1. Set Settings on SD card (or I could set them for you)
2. Unplug Original Lucas 5CU ECU
3. Plug My ECU in (With the programmed SD card in it)
4. Drive Off

Also... Im hoping my ECU will cost no more than $200 for the prototype

Im just looking for ease of installation, ease of programming, no fancy options.. SOMETHING SIMPLE

If you dont program any MAP tables into it, it'll default to an Air/Fuel ratio of 14.7:1

So all the ECU needs to know is the engine size, injector flow rate, how many cylinders AND the RPM to calculate the injector pulse length... and if you cant find that information, your car dosent exist....

 

The Megasquirt is more than that, I priced it out and it was going to run just over $800 for a basic setup, and as mentioned, it required considerable work from the owner to install unless you wanted to pay to have it done, in which case the price was nearly doubled.

 

well there we go.... my ECU costs 1/4 of the price (at the moment) and does the same thing as the original ECU but with the fact that its programmable

 

Awesome news all... Im back at work, should have my prototype up and running by the end of next week (i hope)

@JameyXJ6 if you have any information on the 6CU or the 16CU like wave forms, manuals, diagrams, pin layouts, anything... I'll try and design a V12 model side by side my 5CU version

The 6CU/16CU model shouldn't cost much more than the 5CU model... only because we are controlling twice as many cylinders in twice as many banks, 2 Lambda sensors instead of 1... so i might need to resort to a 2nd microcontroller or use a more powerful one

 

I'm pretty sure I have that info on the 6cu, perhaps even the semantics for the ECU itself. I just have to do some digging in my files. Might take a few days though!

 

Thats ok jamey, ill search the internet for information aswell.. but first... more sleep for me

 

Just bought some parts for the prototype I got a SD card breakout board (for the maps and settings), Another Arduino nano and some breadboard leads... next week I'll be getting a LCD screen and some other parts.. I should have a working prototype reading from the SD card and displaying everything in a months time

I have ideas on how I'm going to enable real-time editing of MAP tables (via the hand controller) and MAYBE a way to interface it to a computer... it all depends on how many pins i have left on my microcontroller....