First, I don't know the whole answer to this. I'm hoping that this can become a small group project where we can step through the code together and figure things out. We'll start with the ANHT hac. The code to which I am referring starts on page 166 and ends on 173. The first segment of code is as follows ...

Right off the bat I am not 100% sure what is happening. But I'll make an attempt in hopes that others will jump in and correct me. The normalized load MAP value is a special MAP value that the ECM uses for doing calculations, comparisons, and such. This is related to the real MAP A/D by 1.18 * A/D MAP-26. It is loaded into Register A and then halved. We then lookup the Integrator Delay vs. Flow (which I believe is a way for the ECM to compensate for the fact that it takes time for O2 to hit the oxygen sensor and that at different airflows the time will vary for when the results of combustion hit the O2 sensor. Is this right? Anyone?). Proceeding further - I get cornfused because I don't get how we can lookup the Integrator Delay vs. Flow when there's no mention of the 'Flow'. It would almost seem that this table is really Integrator Delay vs. Normalized Load Map Value? Is it? In any case we hit the code that subtracts off the R/L Offset vs Coolant. This appears to be a value that is subtracted from the O2mV to yield a lower swing point when in closed loop. True? I know that this value comes from ...

However, I am further cornfused because I don't understand how we can subtract this value from Register A when we don't have any O2mV currently stored in Register A (unless we are creating a negative value to be used later? -- and what happened to the Integrator Delay value??). After subtracting off the Cool Lean R/L value from Register A we then look to see if we are at idle. If we are at idle then we proceed to lookup the Fast O2 R/L threshold at idle constant and then store it to Register A (which overwrites the original value in Register A which was ????). If we are not at idle then we skip to the next line. We look to see if AIR is being injected to the manifolds and if it is then we subtract 100mV (AIR Diff R/L) from the threshold point in Register A. LC9D0 then pushes Register A on the stack orientation so that we can use it later?

Tim

 

Would that be the constant to "control" idle a/f ratio. It would be very nice to control idle a/f ratio seperate from part throttle, that's for sure.


I have a question considering what has come to light. So does ALL this mean that everyone is running 14.7:1 a/f ratio for part throttle(if ecm can compensate). Cause I have read that others run x fuel ratio for part throttle/idle. I guess they are using open loop?

This might sound stupid but I think that it might be possible to "control" a/f ratio via blm update constants. It seems that these tables are related to the topic, at least.!?

 

That constant is exactly the constant I would have told you to change. However, I started this thread in case there is more to it than that. There's a lot of code there. FWIW, there's also a table of O2 thresholds vs. MAP for when the car is technically not at idle.

One of my main questions is what is the difference between fast O2 and slow O2 ... and what is the Error Reference for O2 do/mean?

Those who are running X AFR for part throttle are doing it via either open loop ... or via changing the O2 thresholds. The main thing here is that we don't have a big enough user population with fairly radical setups who actually report on what they do.

Tim

 

It seems like most just go open loop. From what I understand, open loop is considered better for radical engines. I like how the ecm works. So with my "radical setup", I'll try to modify the ecm to work(in closed loop) 100% correct. That is why I've been poking around and stuff. Not ready or willing to go open loop full time.

Doesn't seem like there is many people willing to jump in on this one

 

Haven't looked at this code much, though I've always considered the integrater to be far less important than the proportional part of the loop.

Fast O2 value is the current O2 mv, slow O2 is a less current value(delayed via first order lag filter). The two terms are are compared to give a delta value. This allows the ecm to know if things are going fine, or if the motor is going rich, or lean really fast.


The integrater doesn't seem to have the exact same function as a integral term in industrial process control loops. In industrail control, the integrator repeats the the action of the proportional term.......This really isn't relavent to this post though.

 

The value in reg A is from the JSR:

The lookup routines return the result in reg A.

RBob.

 

Are you still on the 'tuning for dollars' path?

RBob.

 

you must have me confused with someone else. How did you come up with that response from my words you quoted? Let me quote you and tell me how/why you responded that way.... And I'm trying to figure out why you would reply like that. I guess pm me if you would like to clarify. I would hate to see a nice thread like this getting ruined with personal comments. I think it would have been better to contact me directly. Tuning for dollars????? I know others do that but I have not made $1 tuning

 

You asked why more people were not jumping in on this thread. I responded as to why I was not. Seemed reasonable as you like to hear from me. I am not here to train folks to be able to go out on their own and charge for PROM burning.

You are triple x are you not?

RBob.

http://www.team3rdgen.com/modules.ph...ewtopic&t=2357

http://www.team3rdgen.com/modules.ph...ewtopic&t=2394

 

My motivation is CLEARLY to learn this stuff for my engine(as stated before). It seems that you feel differently. That's fine if you want to put some type of spin on something. I guess you would feel better if I didn't post in the diy-prom, cause you have some type of investigation on me. I tried to PM you because I care about diy-prom. It's not cool to fill this board with personal attacks and such. So instead of replying via PM, you decide to fill this thread with JUNK. You didn't prove anything, other that you seem to have a hard on for me.

I guess it would be better if I didn't post in diy-prom. If you are not replying to traxions thread because of me, then that's not fair to him. AND it's not fair to the board because it's not progressing on a technical level. Is it your fault? Well, you seem to feel that I need your responses to "tune for cash". Rbob, you are very talented. If you are not replying because of me, then I will just leave. I don't want any conflicts...


Tim Rotter

 

i like what youve got cooking. I never thought about playing with the o2 filtering rates etc and the airflow vs MV stuff in 8d mostly becuase it hasnt been thuroughly hacked or commented. Id love to jump in but i get more confused then you do with whats going onin the snipets you have up there. . Do you have a whole code snipet you could post. its seems quite likely thats there is a ram adress thats being used that not being mentioned or something along those lines. It coud also be that the HAC is wrong.

Ill ask around and see what i can come up with. If what your onto is what i think your onto then this could prove useful for everyone. Ill see what i can find out.

 

guess this one is DOA......?

 

I don't want it to be DOA but I think it is. My assembly isn't strong enough to attack this yet. Whenever it gets better I'll come back to it. The problem is that when you delve into the really good subjects on a public board it gets really touchy. The advanced good subjects are usually ignored because then those who tune for money can use this knowledge to their benefit in making a name for themselves and to hustle up more business. IMHO, that sucks. More specifically it sucks that Greed prevents other DIY people from gaining more insight. I'm totally against tuning for money ... I've turned down probably 50+ people in the past 2 years (at $300+ a chip you do the math). I'm just not a fan of doing it when I can teach people how to do it.

Tim

 

that sucks......

 

is that part/reason that SDI is banned?

 

That's how I feel about it, I have burnt a few chips for some of the NTTGA club members, but most of them I was adjusting the injector constants. Most times they see how easy it is to do and they feel like they can do it too.
Tim what you posted in here is over my head, so I can not help with this or some of the other post you have made, but I do like reading them and learning from what you and the other’s post here.