i noticed the basic and advanced have many of the same things you can monitor/log. IE: Knock and Battery voltage are a couple. When i log battery voltage on advanced it shows 49- 50, i know this cant be voltage so what is it??!

If i log it on basic it shows a normal 13.8 with the car running. I have read other people seeing way different numbers on knock between the two.
So what is going on?

 

well i found out you should unplug the commander and only log basic or advanced, because all 3 send requests to the ECU in cycles and take turns receiving data. But i still dont know which is better to log, advanced or basic. i've heard basic will show a higher knock then advanced. But I like how advanced will sit between cells on the map trace feature. Basic doesnt do this right? From my understanding basic will sit in one cell at a time instead of interpolating between them.

 

Ok i made an interesting observation and have no idea why this happens.

When i create a watch for advanced battery voltage and start logging it shows 49 - 55 as i mentioned earlier, well looking into the monitor screen it shows the correct voltage for battery (12+) if i look over at "Mafs activity" it shows the identical number as my watch for advanced bat V.

I believe the datalogit is displaying the Maf's activity and not the Bat Voltage. Maybe a glitch in the software? Anyways what is Maf's activity anyways? Battery voltage isnt critical to monitor but i wonder if any other are off?

On a side note i never see more then 1 on my knock with basic or advanced.

 

That sounds odd. My black box with latest DL version freezes the commander when I begin a logging session.

 

Yeah mine does that too. I think its because they are both requesting data from the ecu and they cycle between them which causes the commander to lag behind. I heard its better to unplug it while logging

 

I keep my Commander plugged in. I was under the impression that the DL just interrupts the signal to the Commander. And having basically no knock activity sounds like you have some kind of wiring problem...

MAF activity? that sounds like MAF sensor voltage for another PFC application like a skyline... could be a bug. Sometimes I get the sense that the creators of the DL don't even understand the Power FC that well, beyond the data packets it sends. They seem to include information reported by the PFC without accurately labelling what it is.

 

I agree.

 

IDK on the datalogit yahoo group they have discussions saying that when you log basic, advanced, and the commander plugged in they all request the information so it takes longer for each to get it, and things like knock can be overlooked because it happens so quick.

I know chuck did some tests to see the difference between logging all things compared to a few things, i wonder if he tried it with the commander plugged in.

I have noticed that when logging the commander pretty much does nothing so maybe it is out of the loop at that point.

 

My commander did not work properly with it attached to the DL when I tested it many years ago. So I do not even try it that way anymore as I do not need it that way.
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Did you ever wonder where the MAP REF values come from which are REQUIRED for MAP WATCH viewing only basic or AUX by themselves?

ADVANCE functions has the data. To know which P,N cell the ecu is using/recording it has to know the values for both axis; rpm and ABS pressure.

BASIC only has RPM. But ADVANCE has RPM and PIM v/PIM. Thus when recording ADVANCE by itself or with other features, do not record MAP REF which slows down the logging speed and use ADVANCE in MAP WATCH MAP REF.

When only logging BASIC/AUX, you need to record MAP REF which makes the DL calculate it from RPM and PIM.