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GMPX
April 4th, 2011, 03:18 PM
Well, the moment many have been waiting for, some screen shots of a Cummins truck being logged.
Thanks to Zach at StarLite Diesel who braved the cold to send me some logs from he's test truck. Currently we are in the process of validating the data in these logs, so far everything is going very well with just a few minor changes along the way.

The first picture is a view of the strip charts in the scantool with a 5.9L Cummins log loaded. Because of the way the Cummins ECM scanning is configured, this will not work on any other engine except the CAN based 5.9L.
Whilst most of the values will appear obvious, I'll go over a few of the parameters you can see to explain why data logging and tuning are like beer and pizza, you can't have one without the other.
These charts are totally reconfigurable, you can change the data plotted, the colors, fonts, whatever you like.

On the top row, the RPM and Pedal are self explanatory, the other two values 'Inj Bank 1 V' & 'Inj Bank 2 V" show the voltage levels of the charge capacitors used to fire the injectors.

The second chart shows the three injection pulse times, Main, Pilot & Post. In this case both Pilot and Main were on, Post was off. The other data parameter 'Mode' we are currently evaluating it's purpose (this is beta remember).

The third chart shows some temperature values, boost level and the duty cycle of the Wastegate solenoid.

The final chart shows the 'Desired Rail Pressure', this is what the ECM is commanding, then the 'Actual Rail Pressure', what it really is and the amount of current the ECM is commanding to achieve that Rail Pressure. These are the parameters everyone wants, this is how you see if the fuel system is up to supplying enough fuel for a given injector time. And finally just a simple parameter showing the calculated engine load percentage.

http://download.efilive.com/Software/Images/Cummins_Strip_Small.png

The final screen shot shows what it looks like when you read the DTC's from a truck. This list was from an ECM on a bench harness which is why there is so many DTC's set.

http://download.efilive.com/Software/Images/DTC.png

The scantool testing will probably continue for the rest of the week, during this time I will also be updating the mapping descriptions based on the logged data coming in.

So the final piece of the puzzle is done, not long to go now :hihi:

Cheers,
Ross

07dodge
April 4th, 2011, 04:20 PM
Awesome news! Quick question; have you encountered a maximum value the stock rail sensor or ECM will read to, say 26k or so? If you command more, say 28-29k (why you would command that much, I don't know) how would that affect the ability to tune? Hope that makes sense...

Or any other sensor for that matter. Or is it a matter of finding a sensor that will read higher and swapping it in? Some folks have talked about either the sensor or ECM reading only so high (I think in the 27-28k range)

GMPX
April 4th, 2011, 04:36 PM
The actual math behind the Fuel Pressure PSI calculations in the ECM will go out to over 200,000 PSI or something insane like that, but typically they have limiters in the ECM Operating System that will restrict the values ever going that high.

07dodge
April 5th, 2011, 02:50 AM
So no need to worry about reading inaccurate values either logging or with a gauge then?

THEFERMANATOR
April 5th, 2011, 06:22 AM
Awesome news! Quick question; have you encountered a maximum value the stock rail sensor or ECM will read to, say 26k or so? If you command more, say 28-29k (why you would command that much, I don't know) how would that affect the ability to tune? Hope that makes sense...

Or any other sensor for that matter. Or is it a matter of finding a sensor that will read higher and swapping it in? Some folks have talked about either the sensor or ECM reading only so high (I think in the 27-28k range)

Not sure for the CUMMINS, but I know for the DURAMAX the stock sensor can read up to 180MPA for the earlier ones and 200? I believe for the later ones. You can go in and rescale some of them to make it read higher in teh tuning, or as some have done you can go with an aftermarket sensor that can read ALOT higher and then rescale teh voltage table for it to read the new sensor. I know this has been done for ther boosts sensor as some guys have swapped in ones that can read up to 100PSI of boost and then rescaled the tables to match it.

DURAtotheMAX
April 8th, 2011, 05:22 AM
The first picture is a view of the strip charts in the scantool with a 5.9L Cummins log loaded. Because of the way the Cummins ECM scanning is configured, this will not work on any other engine except the CAN based 5.9L.


Ross what do you mean by "this will not work on any other engine except the CAN based 5.9"??? Meaning you cant scan that many PIDs at once on the 6.7 or SCI 5.9 cummins?? or...?

GMPX
April 8th, 2011, 09:40 AM
It's only for the 5.9L CAN ECM because Cummins do the scanning very different to GM, PID's are not the same between ECM's.

CIDRAUGHN
April 12th, 2011, 08:07 AM
Im just curious as to if the beta testers have found the tables to raise the RPM limit and if those will be on the first release? Its getting close enough to taste it now!

GMPX
April 12th, 2011, 09:32 AM
The answer to that question is yes and no. We've seen changes but not to the point where the limiter is completely gone.
We decided to concentrate on getting the first public release done before revisiting the RPM limiter problem.

Cheers,
Ross