PDA

View Full Version : ECU Diagnostic/Data Logging Gadgetry



lathiat
07-08-2009, 02:15 PM
Howdy All,

Been a while since I updated properly on the status of this, but I made quite some progress on the ECU Diagnostic stuff for my 2nd gen a couple weeks ago, I intend to make a nicer video but I have one here:
http://www.youtube.com/watch?v=hMSnguTxjIs

This shows an LCD cranking out a whole stack of values from the ECU, Accel Enrichment, RPM, Fuel Trims, Injector Timing, Oxygen Sensor, Airflow, etc, etc, etc. It's also not shown in the video but I can crank out all the fault codes at once without playing waiting and guessing games with a test light.

Project is slightly stalled due to lack of working 2nd gen.. hopefully be sorted shortly ;)

A friend of mine with an RX-8 who is also working on this stuff is presently using a very similar platform but to speak to his RX-8, it uses the ODB-2 connector which is the same sort-of hookup that the 3rd gens use - but still using some embedded-style hardware rather than a laptop so you can hide it away and keep it data logging, etc.
For interest: http://www.practicalarduino.com/news/id/331

All in all this is a-lot more gadgety and fun than probably of interest to the more direct car-nuts but hopefully it entertains some of you ;)

And for those of you that don't know, you can get some laptop software & cables to do the same thing for 3rd gens which might be more practical if you're interested at a basic level:
http://www.limitless.co.nz/
Probably set you back ~$100-$150 depending on what cable you get for what features. If you have any questions feel free to ask. Does supposedly support 2nd gens too but it wouldn't play ball for me.

Now I've got that working my first real project of usefulness is to make a fuel consumption trip computer (because the TS doesn't have one!)

Project page:
http://www.geekmyride.org/wiki/index.php/Trent%27s_Magna

Enjoy!
Trent

Razorjack
08-08-2009, 06:47 AM
Hey thats pretty cool. Datalogging without a pc. Never messed around with Arduinos but wouldnt mind to learn if the language isnt too hard. You reckon i could do reasonably cheaply a converter that takes simple serial values(rs-232) and converts it into analogue from a look up table ?

lathiat
08-08-2009, 08:58 AM
Do you mean analogue as in a voltage 0-5V? If so then yeah, that'd be really easy.

Razorjack
10-08-2009, 09:49 AM
Do you mean analogue as in a voltage 0-5V? If so then yeah, that'd be really easy.

Yes.
Thanks for the response. I'll definitely look into it now. Will solve a bit of a conundrum I have.

lathiat
10-08-2009, 09:52 AM
Yes.
Thanks for the response. I'll definitely look into it now. Will solve a bit of a conundrum I have.

Yeah thats not hard.. what are you trying to do?

Razorjack
11-08-2009, 10:30 AM
Yeah thats not hard.. what are you trying to do?
Fairly simple really. Just to send the serial output from my wideband into the piggyback. Then use the piggyback for logging mixtures. That way everything gets logged at the same time. Also the piggyback will expect somewhat nonlinear (using the temp input) values so being able to modify values from a table would be essential. From what I found so far it should be fairly simple (just fiddly) to do ,but of course having never tried this before there is always an if. Thankfully Arduinos are cheap.

lathiat
11-08-2009, 12:06 PM
Fairly simple really. Just to send the serial output from my wideband into the piggyback. Then use the piggyback for logging mixtures. That way everything gets logged at the same time. Also the piggyback will expect somewhat nonlinear (using the temp input) values so being able to modify values from a table would be essential. From what I found so far it should be fairly simple (just fiddly) to do ,but of course having never tried this before there is always an if. Thankfully Arduinos are cheap.

OK well I'm not sure what kindof data you are gonna get from your wideband and the piggyback I'm not really experienced much here. But whether its analog in/out or serial in/out both should be possible - your only likely limitation is going to be the sample rate of the Analog-to-Digital (ADC) convertor.. but I am guessing you will be fine.

Razorjack
11-08-2009, 12:22 PM
OK well I'm not sure what kindof data you are gonna get from your wideband and the piggyback I'm not really experienced much here. But whether its analog in/out or serial in/out both should be possible - your only likely limitation is going to be the sample rate of the Analog-to-Digital (ADC) convertor.. but I am guessing you will be fine.
The data from the wideband is very simple , basically the value of the mixture ie 14.7 at whatever speed its polling , which is fairly low. The piggyback just needs 0-5v or 0-1v depending on inputs, don't think sample rate is an issue.

SupremeMoFo
11-08-2009, 12:43 PM
Sounds like this - http://www.fastchip.nl/Projects/RSTuner.html
and those are cool.