How does one go about disabling long term fuel trims? Tuning in speed density an I'd like to be able to monitor stft so I can play with my maf comp some. JB mentioned doing this and googling didn't turn out even if it was possible

 

Periphery 0 for disabling the rear O2 sensor also turns off the LTFT. In Hex its 0x56D8.

 

That makes a lot more sense...

I have a bunch of stuff marked "rear O2 related" due to that bit and never really looked at it any more then that.

 

That's the address I would create a 1d table with correct? I'm getting deeper into XML stuff more than copy paste .. Just not totally sure how to handle the right answer

 

If you were going to add the hex version of Periphery bits of Periphery 0 it would be-

address - FAA
scaling - Hex16

I'd look up whatever 0/1 style bit that controls the rear O2 and turn that one off

I'll dig my laptop out tomorrow and post it.

 

Ok I have been looking around and searching but got cut short. I came across the detailed periphery bits thread and I'm nearly positive I can find the answer in there for o2 control.

After all this it finally makes sense to me how 2d SD conversion works just as good as a 3d version if you know the nitty gritty. Except 3d can go so far in ve corrections that its exponentially time consuming if you make it. Lol as always the community help is excellent here and thank you all

I've been comparing bits from 8858 which I use and 8859 they look the same after a reasonable glance but ill double check once I find the right bit

Ps you should have a gander at the 88586714 rom , downsized 3d ve table ..

 

Or did I way over think that and now I see "periphery0 Hex" which in my rom has 0x52DA stock and I need to change it to 0x56D8?

 

It wont be 0x52da stock, it would be 56da which means you changed another periphery bit at some point. Basically you'd want 52d8 then.

 

So the 56 - > 52 change was from another bit change and if I just modify the back half of what hex is in there I get the result desired ? Ie da-> d8 essentially stops the ltft + rear o2?

 

I have the rear 02 (bit 1) disabled but i still get lftf trims ( 88570008)

 

If you tune the car first with a MAF (like everyone is supposed to, but doesn't) you can build an entire 3D VE Table in one long drive without lifting a finger, just driving. Its only time consuming if you choose to not use your MAF to do the work for you. You just need to log map sensor KPA along with your MAF readings. You will need a version of Evoscan with Live Map Tracer as well.

The only thing I have noticed that will make the conversion inaccurate is a poor MAF intake setup with turbulence.

-Jamie

 

with two threads going, its getting hairy, but I do have v2.9 and I can set up a MAF rom very easily, my MAF is just dehoneycombed so maybe that will hinder things.

I have a fp84 intake tube

 

I would use a standard honeycombed MAF for testing.

-Jamie

 

It might be 56D0 which is also the immobiliser. Todd I will look at my notes but I am pretty sure that 56d8 should turn the LTFT off as well. I have them off in my ROMs but I couldnt tell you when I turned it off...or how Well at least for sure.

 

Ive a 9 ecu in an Evo4 with no immobiliser / no rear o2 so im using 56d0

56d0 immo / rear o2 OFF
56da immo / rear o2 ON
56d8 immo ON / rear o2 OFF
56d2 immo OFF / rear o2 ON


52 rather than 56 would be " IGn Timing as map "
16 rather than 56 would be "o2 heater circuit OFF "