If I'm reading correctly -

INT = Integrator 'value' - Anyone have any better explanation as to exactly what this is? Mine is staying at 128, no matter what.

Now, BLMs on the other hand = Block Learn Memory? - When this is reading over 128 (the INT value? or just a coincidence?) = lean

Over 128 = lean
Under 128 = rich

Is that correct?

How is the BLM determined? ecm adds X fuel for Y lv8 value, checks O2 to see rich/lean, and modifies the fuel, and gives teh BLM to show how much was added/subtracted?

Also, in my BLM + INT searches, I've notices a lot of talk about VE cells in relation to BLMs - I take it that this is a SD setup thing? (VE tables in relation to MAP readings)

 

Also on a side note, do I want to be looking at raw or sensor BLM data?

Because I'm running at 45-46 blm (sensor) at idle right now, with 9.92 g/s of air being pulled, @ 1000 rpm idle (stick, and yeah, it's a little high).

Also need to re-adjust the TPS - I seem to be running at -0.3 as the tps reading? (less than .54v it seems)

My CTS is reading like -38.7, and I'm getting a code 15, so I also believe I need a new CTS - that'll be going in soon... probably before I actually start adjusting my fuel, as I'm sure I'm adding in some extra fuel due to a 'low coolant temp'

 

Anyone?

 

Yes, greater than 128 means lean and less than 128 means rich.

I don't totally understand what INT means, but here's what I think it means. If the O2 is reading lean, then the INT immediately goes up and starts adding to the BLM term. 128 is only important because it's the mid point of numbers that can be represented in 8 bits. BLM is a multiplier, so 128 equates to 1. Numbers lower than 128 are between 0 and 1 and numbers greater than 128 are greater than 1. I don't know what the exact mapping is (256 could be 2, or it could be 10, depending on the software).

Anyway, in the case of INT, I think 128 equates to zero and numbers less than 128 are negative, greater than 128 are positive. So when you look at the INT values, you can tell if the BLM is being increased or decreased. When INT comes to 128, it means the loop has converged and the BLM is done changing. The INT is the error signal that is adding/subtracting to the BLM while the loop is in flux.

This is what I think is going on. I may well be wrong and will gladly take a correction from the gurus of the forum.

 

Interesting... by that case, then the INT value affects the BLM value... again, though, are we to be looking at the RAW or SENSOR BLM data from WinALDL?

Also, it would seem that you can't have true BLM value, until the O2 sensor warms up, and you go into closed loop mode, yes?

 

Are you using WinALDL? If so, raw and sensor are the same. With some stuff, WinALDL converts raw data into more useful units (like degrees for CTS, or % for TPS), but not with BLM or INT.

The computer will still have its old BLM values when it's cold, but you won't get fresh BLM/INT values until you go to closed loop.

 

I am having tons of problems trying to get my ecm to talk with my setup. I have read through mounds of article and threads, but I am still having problem. My BLM's with the car in closed loop, vehicle in gear with my foot on the brake read from 140 to 145. This would indicate a rich condition. I should mention I am running 24# svo injectors running at 53psi. I have the injector constant bumped to 30psi. The injector constant has been moved from 24 through 30 and the car doesn't feel right. Any thoughts on what I should try. I know this is a little more than what was in the origional post, but I thought I would give you (Mastiff) a try before asking the rest of the board. Any help/direction is greatly appreciated.

 

Your car is running extremely lean if your BLM is in the 140plus range. Bump the injector constant down to 24 and go from there. Give the car time to change the BLM values in closed loop. Take it for a good 20 minute stop and go trip to give the ECM time to relearn.

 

Thanks for the tip. What do you think about the fuel pressure. Is it wrong to run at 53psi or should I bump that down as well?? Also how high can the injector constant safely go???

 

Thread hijack!!!

 

Oopps! Sorry about that. I get ahead of myself when I hear people talking about problems that are similar to mine. I will try and remember to post individually from here on in....

 

INT=short term fuel trim
BLM=long term fuel trim

INT's above 128=lean
below 128=rich

BLM tries to keep INT at 128 as best it can by adding or subtracting fuel.

BLM's above 128 means it's adding fuel to INT to get to 128 and
below 128 means it's subtracting.

so in terms, INT and BLM readings are opposite in meanings when determining your tune and adjustments.

using 6E, i have found lowering the inj. constant slightly, not raising it, will richen the mixture across the board. i would also lower the pressure to around 46-48psi to keep the strain off the fuel pump. hope this helps a little.

 

Awesome - thnks a lot. I will be sure to give those a try this weekend. I have been scratching my head over this issue for some time now. I am running a MAF setup, so the computer does adjust for any far off BLM requests. However the occasional 145 and 135 BLM values were getting me concerned. Should I also disconnect the battery after changing any values - or is that step not necessary???

Thanks for the help.