Fuel Volumetric Efficiency map tuning problem

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UNISA JECS
 

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Re: Fuel Volumetric Efficiency map tuning problem

Post by UNISA JECS »

Ok Matt I finally re-installed my Type 4 ECU today and did some testing and at first the VE tracer was not working as in the past I had modified my VE LOAD and RPM values, so this leads me to the question why is it that what it appears to be if you modify the VE LOAD and or RPM scales the VE tracer will be off? However when I put these VE LOAD and RPM scales back to stock the tracers seems to work at idle and I did my best to give a little bit of steady state part throttle and play with the VE table which appears to work ok

Is it important not to modify the VE LOAD and RPM scales then?
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Matt
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Re: Fuel Volumetric Efficiency map tuning problem

Post by Matt »

at first the VE tracer was not working as in the past
The VE map tracing uses the TPS voltage as the index to this map. When you adjust values at the cells highlighted, your injection time should change accordingly. Do you see this?
I had modified my VE LOAD and RPM values
From my investigation I found that the VE table is TPS vs RPM base. There is no 'load' indexing to this map
so this leads me to the question why is it that what it appears to be if you modify the VE LOAD and or RPM scales the VE tracer will be off?
You should not modify the TPS indexing for this map. Nistune now reads the 'adjusted TPS' value directly from the ECU. It then uses this value to see where in the VE TPS scale the value is indexed and uses this for the tracing.

I would not expect that the maptracing should go out if modifying that index (I did not test modifying the TPS scales) but I did check a range of ECUs which uses the VE map that the tracing was correct, by modifying cells which were highlighted
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Re: Fuel Volumetric Efficiency map tuning problem

Post by UNISA JECS »

Matt wrote:
at first the VE tracer was not working as in the past
The VE map tracing uses the TPS voltage as the index to this map. When you adjust values at the cells highlighted, your injection time should change accordingly. Do you see this?
I had modified my VE LOAD and RPM values
From my investigation I found that the VE table is TPS vs RPM base. There is no 'load' indexing to this map

Sorry what I meant was I modified my VE TPS and RPM scales
so this leads me to the question why is it that what it appears to be if you modify the VE LOAD and or RPM scales the VE tracer will be off?
You should not modify the TPS indexing for this map. Nistune now reads the 'adjusted TPS' value directly from the ECU. It then uses this value to see where in the VE TPS scale the value is indexed and uses this for the tracing.

I would not expect that the maptracing should go out if modifying that index (I did not test modifying the TPS scales) but I did check a range of ECUs which uses the VE map that the tracing was correct, by modifying cells which were highlighted
In this short video I put back the VE TPS scale back to stock but I left the RPM scale alone which is not stock and so far it appears to be following the trace correctly, I still need to actually take it for a drive but I did give a little throttle input to move the trace around and mess with the fueling to invoke a change in my AFR's and it does so far.

http://youtu.be/wjMC_rVJnu4?list=UU3Awy ... Dg-FTp1oaw
UNISA JECS
 

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Location: USA Socal

Re: Fuel Volumetric Efficiency map tuning problem

Post by UNISA JECS »

Found another issue while in streaming mode the VE MAP tracer does not follow, it will only stay in one column and go up and down according to RPM.
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Re: Fuel Volumetric Efficiency map tuning problem

Post by Matt »

Yes it will not work in streaming mode. The index value is directly read from the ECU. It is not available in the standard streaming list of registers to perform tracing on (previously I attempted to use the TPS voltage for indexing but now it is read directly)
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Re: Fuel Volumetric Efficiency map tuning problem

Post by UNISA JECS »

Matt wrote:Yes it will not work in streaming mode. The index value is directly read from the ECU. It is not available in the standard streaming list of registers to perform tracing on (previously I attempted to use the TPS voltage for indexing but now it is read directly)
How would one make changes to the VE map, would it replay in a log and trace that way?
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Re: Fuel Volumetric Efficiency map tuning problem

Post by Matt »

In tuner mode select as few registers as possible to speed up the tracing if you were wanting to log it
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