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Discussion Starter #1
Hi, all!

Does anyone have a list of specific PIDs that can be used with Torque or similar app?

I have a Car Scanner Pro set up on my phone with various useful info, but I want more. Specifically what I want to see is:

-KCLV (Knock Correction Learn Value)
-KFV (Knock Feedback Value)
-O2FT B1 and O2FT B2 (fuel trims commanded by REAR O2 sensors, when rear-O2 CL mode is active)

The first two I can see in TechStream, and the last one is extensively mentioned in FSM which guides you how to access it with intelligent scanner tool (or whatever Toyota calls it), but I haven't seen it in TechStream. Still It is very interesting to see these values under various modes.
 

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Here are two 4Runner PID data points for the transmission: torque converter temp, pan temp. Should work on the FJ ECU.

Reference: Toyota-4Runner.org

PID: 21d9
Long name: Transmission fluid temp 1
Short name: TFT1
Unit type: *C
Max/Min: 220.0/-40.0
Equation: ((((E*256)+F)/256)-40)*1.8+32

PID: 21d9
Long name: Transmission fluid temp 2
Short name: TFT2
Unit type: *C
Max/Min: 220.0/-40.0
Equation: ((((G*256)+H)/256)-40)*1.8+32
 

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Xsen -

I'm also very interested in any info about:
-KCLV (Knock Correction Learn Value)
-KFV (Knock Feedback Value)

Is the ECM constantly adjusting ignition timing advance to keep it right on the edge of detonation, and what are the limits? (e.g. is "learning" a continuous process?)

Reviewing many hours of Torque Pro logs, I see a hard advance limit of 39.5 degrees on my '14, and I'm curious if this is is a fixed max value across all dual-VVTi model years.
 

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Discussion Starter #4
Well, I can't say for sure about dual-VVTi engines, but here's what I know about this. Bear in mind that all this is just a result of my own research and it may or may not be what's really happening in the ECM. All maps and tables are taken from a 2007 FJ Cruiser ECM, OS id 3YWG29, viewed via HPTuners VCM Editor. This probably was a SC vehicle.

So, Toyota calculates SA from several sources:

Desired SA = Base SA + KCLV Value + Knock F/B Value + Compensations

Here's an extract from what does look like a Toyota document (though I never found the exact source) that was posted on Lexus IS forums that describes this logic:
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I've seen this algorithm work on my FJ when I switched from RON95 to RON100 gas, my KCLV went up a few degrees after a few days driving.

Both KCLV and KFBV are displayed in the Techstream SW, so we can assume that this is relevant. What we don't get to see is the Base SA and whatever Compensations are applied, as these are the stock engine calibrations made by Toyota (and not intended for general public to see anyway)

This is where it gets a little complicated as we have to trust that HPtuners' definitions are correct.

Let's talk Spark Advance first, as this is what largely gives us torque and horsepower.

According to VCM Editor our Base Spark Advance map looks like this:

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Besides this HPT defines two more Base maps - one for High Octane and one for Low Octane:
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Here's how HPTuners defined these maps:

High Octane Spark vs. RPM vs. Load: This table is the upper limit for the knock learn interpolation, it is used in the knock correction calculation when there is no knock detected and the knock learn factor has adapted to 0. In some applications his table limits the maximum value of the base spark.

Low Octane Spark vs. RPM vs. Load: This table is the lower limit for the knock learn interpolation, it is used in the knock correction calculation when there is large amounts of knock detected and the knock learn factor has adapted to 1.

This is where I am a bit lost as there is no info on when would ECM use the Base Spark map vs when would Base SA be interpolated between the HO and LO maps.

There are various compensations defined as well, based on VVT, ECT and IAT. I'm absolutely positive that there are more compensations, for example based on cat temp, but we can't see those (yet?).

And yes, there is a Maximum Final SA defined as 44. (Yours is probably different as it's a different engine). There's no MBT spark map, which could be awesome to see.

Switching to Spark Retard, here's what we see in the editor:
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Look at the Knock Adaptive Learning section. I believe that this is where KCLV is defined with a max value being 29 and start value being 21. And the Knock Retard section does look like KFBV, being at -3 by default. The offset value below is supposedly used to offset the HO-LO interpolation result when used in the knock correction calculation. But the exact calculation form is unknown at this time.

My current understanding is that FJ could do much better in terms of spark efficiency. I do not know why would Toyota calibrate the engine this way and not use more SA to improve overall engine efficiency and performance, and I suspect that's why Raptor managed to raise the entire torque curve (at least that's what they claim).

It could be very useful to log the vehicle under various conditions and build a histo of Applied SA vs RPM vs Load. From there we could move on to building new base maps. But. alas, NA 2007 FJ is unsupported, and even for supported OS ids the available tools list is quite limited at least for now. For example we don't see anything related to rear O2 sensor closed loop operation.

BTW, your dual-VVTi engine should also have a more sophisticated VE calculation as your exhaust camshaft is variable, therefore it is certanly used for EGR control and operation.

If only we could get some reliable info on how Toyota ECMs function and a complete definition file...
 

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Discussion Starter #5
Thought I'd update.

KCLV and KFB can be monitored by HPTuners' VCM Scanner (use latest beta). What's even better - it can build histograms on the fly, and that's a powerful thing. Here is how it looks like:

Knock feedback value:
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Knock Correction Learn Value:
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X-axis is RPM/1000, Y-axis is Absolute Load in %.
This was logged on RON100 pump gas. I also logged another FJ running RON95 pump gas, let me tell you - it sees ALOT more knock feedback, and KCLV is lower. Can't post the screenshots, cause I managed to screw up the log saving process.
 
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