Seems like we needed nine months to figure this table out -lol
https://www.evolutionm.net/forums/sh...3&postcount=13

I have a question with two USDM 2004 VIII's, one 96420008(7), the latter 94170014 the air temp comp tables are scaled to such,


Now 41ۨ C is quite a bit off from 82ۨ C, and they have no scale relationship to each other so it has to be a real temp difference. All I can think of is the car was to be shipped for the Alaska market - lol. Any ideas

 

the one on the left is the same as on the FQ340 fitted for the island's climate

 

Bump for a good topic, and one that is pertinent when we log cars in different seasons.

Also I thought I would add this as well. Its a PM I converted into a how to for those that want to log these values as well--

These are not necessary to understand whats going on in your engine for the most part. They can be helpful in seeing the effect of weather on how your ECU decides what its going to do. The values listed are for the US IX type 15 ROM, though I suspect that you will find any ECU follows a fairly close pattern and the values wont be too far off (within a few hex values). Remember the High bit is even and the low bit will be odd.

First you need to add the MUT table if you havent already. Secondly, you need to get used to editing xml.

Its pretty basic actually once you get going with it actually.

The "Raw 2byte Load" is 6b42/43. The other 2 variables are (in hex) 6b46/47 and 6b48/49. These are for the Load+Baro and Load+Baro+Temp. What I would do to use these is when you add the MUT table go to MUT 4x, and in 40 and 41 put in the first 2 hex values and then in 41 and 42 the others.

Once that is done save the hex and sooner or later you need to flash the car again obviously. By the way the 46/47 is the Load + Baro, and 48+49 is all 3.

Then in EvoScan clone the line (copy, ctrl+C, etc.) for 2 byte load and then paste 2 copies. Change the request ID1 and ID2 to the new MUT values (which is what its calling up) in this case 40 and 41 and then the second line to 42 and 43. You need to name them something different than just Load. I have Load, Load+Baro, and LBT for mine. The log reference tag also needs to be changed and you can do load2 and load3 or LB and LBT or something to tell them apart. I would make sure that the lines are also right under your normal 2 byte load line so that they log right next to each other as well.

Enjoy.

 

Bump for someone with time to expand on the process or write a simple walkthrough for what JB is talking about.

I want to be able to log the additional variables, but don't know where or how to get the MUT table!!!

Additional information would be appreciated!!!

 

basically get your raw 2byte load, and then add 4 for baro and 6 for baro+temp

ie if you load raw is 0x6b42
then baro compensated load will be 0x6b46
and temp+baro comp load will be 0x6b48

should work for most, you will soon see if its not correct

 

Ohhh, ok. Correct me if I'm wrong, so I can go and do the same procedure I used for the raw 2byte load but then just change the hex values you have pointed out?

I just looked up that thread and the stuff is a bit different, can you please expand Tephra, JB, anyone?

 

Or if you only have the 2 byte high and low added to your xml then you can use the following numbers:

Load+baro+temp= 27464/27465

Load+baro=27462/27463

 

Ok, those numbers seem to be inline with what the raw 2byte load procedure uses.

So, JB, I take it that the first number is the high and the second the low, is this correct?

Thanks

 

That is correct. They are in order and an easy way to check is the current numbers you have for the raw uncorrected 2 byte load as well.

 

Bringing back an old thread... it makes sense that the load for timing lookup doesn't drop after 25C IAT, otherwise, a heatsoaked IAT could cause detonation when lots of cooler air suddenly enters the engine. This seems to be the Mitsubishi way as there are parallels back to the DSM's code. Implication for my MAT into IAT SD arrangement is that these limits will be hit earlier, so there may be an area around say 20C IAT 25C MAT where you would still get load varying with MAF but not SD unless we change it.

The fuel lookup doesn't matter terribly much since it is a ratio that varies little from cell to cell compared with timing. The air mass that is multiplied by this ratio IS temperature and baro compensated separate from the load calculations.

Boost calcs - I think the ECU is going to aim for more boost (to hit the same temp compensated load) at high IATs to keep the output up on a stock car when it has much spare capacity.

 

Does anyone recall what the requirements are for the ECU switching between the 3 loads? As I recall (and cant find the thread) one variable is the temp which I wanna say was 60*F, the Baro would I assume be another facet. Since the SD Roms run (or can run) with fixed values for temp and baro (i.e. too lazy to wire my GM IAT from my MAFT Pro in) I am trying to remember what the conditions were. I know Dave has probably told me numerous times since before this thread was even around, perhaps once more unto the breach?

Havent forgotten, just have too much to remember