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If you had to chose to replace P sensors, you would want:


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I guess I should have quoted your original question, for "posterity". At any rate, I do hope you find what you seek. Good on you my friend.
:D

Joel in the Couve
 

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Other OEM as I would expect it to be contemporary and more reliable as well as ironing out some glitches - according to reports. The configurable option sounds great, but I suspect would involve a lot of time and effort as well as some high tech diagnostic equipment. If someone has a plug and play option great! Also cost factor. Related question. The low rpm miss fire that has been talked about. Does this get worse as the bike ages, if so is it indicative of an imminent sensor failure?
 

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Discussion Starter #5
I completely understand the rationale in using OEM parts, and am not against it at all. The main problem I see with that though, is finding appropriate OEM sensors, like the Suzuki sensor mentioned in another thread, which will work and keep working. Keep in mind the Suzuki sensor was not designed with turbocharging in mind; I worry that continual exposure to boost could damage, or otherwise shorten its lifespan. Also, the Pign sensor used on the 500T is a 12v input part and this will make it likely impossible to find a drop-in replacement for.

Without going into too much detail, I am in talks with people off-site about design and fabrication regarding the latter options in the poll. They both would have an interface to a computer, likely over USB, which would allow the user to 'tweak' the module in order to fine tune it, and possibly fool the ECU and allow some ability to tune the air/fuel mixture. The 'all-in-one' option, replacing all 4 sensors with one module, will probably have a variant that would incorporate the (optional) ability to process input from a wide-band lambda sensor thus allowing one to 'target' a specific air/fuel ratio. It may support some other features I'm not going to discuss at the moment. And, if things go as planned, either option would be entirely reversible and non-destructive to the wiring harness (and hopefully the bike too ;)).

Price-wise, my thoughts are that the 'replace individual sensor' option would probably come in at around $90, but that's just a preliminary assessment based on parts and production costs, and my perceived market value. The 'all-in-one', I'm trying to target around $250. The prices may seem a bit high but the utility of it, being able to 'tune' it, might be worth the extra cost... and the price doesn't seem too out of line from what one would expect to pay for a brand new P sensor, if they were available at AutoZone, for instance.

Still, I'm interested in peoples' opinions about this.
 

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Discussion Starter #8
Okay, there's a little interest.

We're still nailing down components and the tuning software.

Here's a teaser for some things we're trying to achieve with the 'single' sensor unit; the multiple sensor unit will likely be similar and may have some more twists.

Hardware:
- USB interface to the hardware; should be automatic, 'driverless' installation for most people.
- Source MAP sensor can be on-board or external, the latter permitting the use of OEM / off the shelf sensors.
- Faults within the system will cause the ECU to enter limp mode and display a fault indication on the dash and its LEDs.
- Store and report faults to the tuning software.

Tuning software:
- Windows version or possibly Java version that should run on Windows, Linux and maybe OSx.
- Automatic generation of the curve for the source MAP sensor with minimal user input; i.e. for external or custom sensors.
- Adjusting the curves of both the source MAP sensor and the output to permit adjustments / fine tuning.
- Live monitoring of the unit's operation when connected.

And I'm still looking for suggestions or comments.
 

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- Windows version or possibly Java version that should run on Windows, Linux and maybe OSx.
I find it appropriate that I made this little image yesterday.

hatejava.png
 
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Discussion Starter #10 (Edited)
Thanks for the input.
I was hoping for something 'constructive', but any criticism is helpful.

I have Windows, Java and Android app developers on board.
I can get an Xcode developer if the demand is there.

Otherwise, it is what it is: Windows first and whatever next.
 

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Discussion Starter #11 (Edited)
Anyhow, the factory's specification are (key on, engine not running)-
P1 & Pb: 3.13v to 3.73v; or in other words 3.43v +/- 0.3v
P2 & Pign: 1.09v to 1.29v; or in other words 1.19v +/- 0.1v

Pb has a 2-3v window (2.5v +/- 0.5v) with the engine idling.
Pign has a 0.43-0.83 window (0.6 +/- 0.2v) with the engine idling.

We're still settling hardware, but what we're looking at is capable of output resolution better than +/- 0.1V accuracy.
... we're looking at things with better than 0.05V accuracy, to be honest.
 

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Thanks for the input.
I was hoping for something 'constructive', but any criticism is helpful.

I have Windows, Java and Android app developers on board.
I can get an Xcode developer if the demand is there.

Otherwise, it is what it is: Windows first and whatever next.
I was constructive. I voted on the poll too. I would think most of us just want stock, plug-n-play. I have other stuff for modding - this one stays originalish.
 

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I once build a replacement sensor using the Arduino platform.

The question is not if it is accurate , the problem with software is , will it run stable.

When it fails ( the software ) what happens? With the wrong output it can destroy your engine.

Computers do strange things in an automotive environment. Sparks, Coil pulses, Relays etc etc

I myself wouldn't be comfortable to sell a software system without more then let say a 95% knowledge of the system I am programming.

I always wondered the computer systems for let say the space shuttle were 3 independent computers have to vote over actions to be taken ;)
 

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Discussion Starter #14 (Edited)
Pim- We're still settling on hardware specifications and although the prototype may not use automotive qualified parts, the final product will. Also, watchdog will be used to catch misbehavior, probably an MCU sampling the outputs and comparing those to the commanded output.

I've brought up possible failure modes and how to handle them. The goal is to fall to a condition like what would happen if one of the sensors fail- cause the ECU to enter it's "limp" mode.

The Space Shuttle had redundant computers because human life was at stake. Most automotive applications usually don't have redundancy.
 

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Discussion Starter #15
I was constructive.
I fail to see how posting a picture trash talking about Java, and not suggesting any alternative, is constructive.

I voted on the poll too. I would think most of us just want stock, plug-n-play. I have other stuff for modding - this one stays originalish.
I'll grant you that, that most want something stock, but where's the NOS for these sensors?

Is a zuk sensor 'stock'? Is using the zuk sensor much different than using something else, if it works? Are you violating any warranty?
... well you are if you buy a new zuk sensor and use it on the CX and it fails since it wasn't used on a zuk, but that's nit-picking.

Plug and play... okay. What's the cost of a new Pign sensor?


I wonder if the creators of Ignitech and such faced such opposition as I'm getting?
(Yeah, that's an exaggeration. But still.....)
 

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I do want to point out... in case you missed it...:
tractor running msp430
I like a system running on a RISC processor. I worked for more then 10 years on 3d design software running on a UNIX platform and a RISC processor and in all those 10 years it maybe crashed 5 times !

Although I learned programming Pascal in the 80's ( similar to Arduino ) , I have no clue about the current available systems and their capabilities and problems, stability etc.

More then 2 years ago I mentioned designing a direct replacement sensor ( plug and play ) but I didn't get much response :

CX Forum - Alternative senor

The mayor problem for a plug and play sensor is that it should run on the power supplied by the ECU and that is 4.75 Volt - 5.25 Volt. This with making the sensor idiot proof : reverse voltage protection, too high voltage protection, wrong connection voltage is very difficult. You need all these protection because people are going to test your sensor with all the consequences.................



We're still settling hardware, but what we're looking at is capable of output resolution better than +/- 0.1V accuracy.
... we're looking at things with better than 0.05V accuracy, to be honest.
A small remark on your accuracy. The OEM sensors are radiometric, if the supply voltage is higher , the output is also higher. This is compensated by the Analog - Digital conversion which basically compares the supply voltage with the sensor output. So if you want to be accurate , you have to also measure the sensor supply voltage en compensate your output.
No point having a perceived accuracy of 0.05 Volt ( 1% of 5 Volt ) when your sensor supply voltage has a accuracy of only 5% ;)
 

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Discussion Starter #18 (Edited)
I like a system running on a RISC processor. I worked for more then 10 years on 3d design software running on a UNIX platform and a RISC processor and in all those 10 years it maybe crashed 5 times !

Although I learned programming Pascal in the 80's ( similar to Arduino ) , I have no clue about the current available systems and their capabilities and problems, stability etc.

More then 2 years ago I mentioned designing a direct replacement sensor ( plug and play ) but I didn't get much response :

CX Forum - Alternative senor

The mayor problem for a plug and play sensor is that it should run on the power supplied by the ECU and that is 4.75 Volt - 5.25 Volt. This with making the sensor idiot proof : reverse voltage protection, too high voltage protection, wrong connection voltage is very difficult. You need all these protection because people are going to test your sensor with all the consequences.................
My first programming experiences were Applesoft Basic and UCSD P System. I miss 8" floppy discs.:rolleyes:

The system we're planning is based on a 16 bit, low-power, RISC processor.

I'm a bit worried about powering the actual unit off the ECU's outputs. It could lower the voltage on the rail and thus affect the output because... read below.
A small remark on your accuracy. The OEM sensors are radiometric, if the supply voltage is higher , the output is also higher. This is compensated by the Analog - Digital conversion which basically compares the supply voltage with the sensor output. So if you want to be accurate , you have to also measure the sensor supply voltage en compensate your output.
No point having a perceived accuracy of 0.05 Volt ( 1% of 5 Volt ) when your sensor supply voltage has a accuracy of only 5% ;)
The plans are to use the ECUs output, the voltage on the connectors to the sensors, as the reference for the outputs of the unit when substituted for the P1, P2 and Pb sensors.
Pign, as you know is a curious beast because of it's >8v supply, and it's reversed output.

If you'd like to be involved with this, I would be honored. Your knowledge of the bike's systems would be immensely valuable.
You could be the European source for it. ;)
Send a PM if you want.
 

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Discussion Starter #19 (Edited)
I wonder if the ECU can source 30mA on its sensor power source....

... to clarify, the processor we're looking at draws less than 10mA and the outputs draw around 5mA, but a little headroom never hurts.
 

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I wonder if the ECU can source 30mA on its sensor power source....

... to clarify, the processor we're looking at draws less than 10mA and the outputs draw around 5mA, but a little headroom never hurts.
I measured once the current draw by each sensor and it was around 8mA. So 8 x 3 = 32 mA :rolleyes:

The input of the ECU is around 100 Kilo Ohm
 
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