This Base Low Coolant Temp Timing Trim Map *looks* like it's what makes Evos run like crap when they're driven cold...and it *looks* like setting the entire map (all 3) to 0's may fix that. Is that what we're saying here? If so, this is great news!

 

Yes, if you zero them out, or try just zero-ing the coolant temp control map so the maps never kick in, it will make it alot better when the motor is cold.

 

Some interesting maps of fan:

 

Pd1, see this post on the best way to disable the low temp coolant timing trim:

https://www.evolutionm.net/forums/sh...40#post6063440

This is the best way because the code is skipped and thus saves a few cpu cycles. Its also much easier to implement.

 

Interesting indeed. The IX SE USDM map appears to be the same as the JDM RS map

I'm guessing the fact that the off condition is blocked to 100% makes it similar to the lean spool/wgdc on/off tables where this just disables the ecu's ability to raise the value above 100%. I still haven't quite figured out the on conditions yet. I can't tell if the on1/2/3 set is for the main fan and the a/c1/2/3 maps are for the push fan/ac fan or if they are relative to running with the ac on or off. My guess is the latter simply because the push fan would be on all the time if that was not the case. I wouldn't be surprised if the on1 and ac1 conditions were for idle and neutral, but that is just a hip-shot. If that were the case column 3 for each could possibly be for when the other fan was running also (just guessing that by the fact that the ac duty is lower in this block).

 

So you know some of the conditions. My GT-A only has 3 columns. On , Off , A/C.
On is the on temp for the main fan. Off is temp to drop below before the fan turns off so it has hysterisis. A/C is the main fan duty while the A/C fan is running. The reason it sits higher is because the fan will run regardless of the engine temp so long as the A/C is on, to assist the cooling of the A/C unit. I haven't bothered to check, but my car has only a single cooling fan so for all other evo's the other columns will be for duty for the second fan.

It's easy to check. Change duty of the fans so they come on at 2 degrees higher one at a time and watch to see which fan turns on at the new temp. Do a little experiementing and you will find it in a couple of minutes.

 

I would agree, so long as you're not already using the FAA to disable something else. Thanks, though. Great find and great work, as always.

 

Check this post:

https://www.evolutionm.net/forums/sh....php?p=6068354

 

Outstanding! Now if we could just disable that pesky P0300...

<ducking>

 

That is pretty nice!!

So if we want to skip cold running timing maps, we just set bit9 to 0?

 

Yep.

 

I tried "=" 0 and it wouldn't work so i hit the decrement button with the bit9 cell highlighted and it outlined the other areas as if they were changed but only bit 9 changed to 0.....but its showing like the other cells have been modified but they all stayed the same?

anybody else notice this?

I just zero'd the maps out for now....

 

That is normal. When you change the value of one bit, the other 7 bits will also show as changed since they represent the same ROM address.

 

Actually, that's not normal. Its not working properly. Don't use it. I hadn't actually tried changing a bit, so I wasn't aware that its not working. I'm working on a fix.

 

If you open the orininal ECU_PEREPHERY 0 - 4 tables and then edit one of the bits in the new tables, it does highlight the surrounding box's as stated above.

However it does put the correct code into the original ECU_PEREPHERY 0 - 4 tables.

For example in ECU_PEREPHERY 0 my code was 56D0, I changed bit.11 (Disable EGR / Enabled Ign Adv (set bit=1)) to 1 and change bit.9 (Enable Warmup Ign Retard) to 0 and it changes ECU_PEREPHERY 0 to 5CD0.