I tried the correction interval set at 3. I like it better. Less oscillation. With the Ingersoll solenoid (same as Perrin), I don't recommend an interval of 1 as listed by mrfred.

 

I'm having an issue of not being able to get any closed loop response out of my system. I'm using MR Fred's instructions w/ a GM 3 port w/ 10ohm resistor.

I've got the same values as MR Fred for my BCS & correction interval, and i'm pretty sure I've followed the instructions verbatim (but I'll double check today).

When I log boost Error, I just get -3.xxx psi as a constant value as if it's not reading boost or my set values are too high. I have my desired boost set to absolute pressure or 22 psi + 14.6 psi in the two boost tables.

I can log boost and my evo X m.a.p. sensor is reading fine right around 22 psi or so.

Is there anything you guys can point me in the direction of that could help make diagnosing a bit faster?

Thanks,

Eric

 

Did you set your WGDC?

 

yes, i've got that dialed in to run fine and it's holding boost fantastically at 22 - 20 psi. So i'm not in a mad rush to fix it because it works fine, but i do want to have the closed loop control eventually

 

Found a silly error on my part.

My address for SHLR->SHLL for EBC was not set correct.

I'll upload the change and see what happens.

 

As long as there is nothing else overlooked, fixing that will solve your issue.

 

Bingo.

Feedback is working. Now I need to fine tune it. I'm getting a little oscillation in the system, part of which I think is due to a Baseline WGDC that is too high that starts everything off, and maybe a bit too aggressive Boost Error Correction Values.

mrfred...

is there a way to adjust the boost error correction values to have greater resolution than what it currently has? Instead of going from 64 to -63.5 in units of 0.5, I'd like it to go from ~-25.5 to 25.5 in units of 0.2

Thanks,

Eric

 

mrfred...

In regards to my previous post, I've done a bit of research (not sure if it's right or wrong) in the xml files and have a question in the scalings...

I have two sets of the same name (see below), the 2nd is the one i was meant to copy in from your first post as part of the instructions, but the original had the increment set to 0.1

<scaling name="OffsetWGDC" units="%WGDC Change" toexpr="(x-128)/2" frexpr="x*2+128" format="%.1f" min="-64" max="63.5" inc="0.1" storagetype="uint8" endian="big"/>

<scaling name="OffsetWGDC" units="WGDC Change" toexpr="(x-128)/2" frexpr="x*2+128" format="%.1f" min="-64" max="63.5" inc="0.5" storagetype="uint8" endian="big"/>

1st of all... do i need both of these or was this something that was likely included with a recent version of ecu flash?
2nd... does this mean the variables have enough room to simply change the increment from 0.5 to 0.1 without changing the max and min?

If the answer to my 2nd part is no, then i think the only item calling for a value outside of the +/- 25% range is the "max total WGDC downward correction" which has -64 in it. If i need to change the max and min, does this risk any harm in raising this number to ~-25.5 or whatever I use for units?

Thanks ahead of time,

Eric

 

Either definition is fine. No problem to keep both or toss one. You'll not see much effect of incrementing the duty cycle by anything less than 0.5%.

Max total downward correction: The BEC table is an incremental correction to the WGDC. The "max total downward" correction is the sum off all the incremental WGDC changes made by the ECU during each boost session (it resets when you let off the gas). Its always relative to the baseline WGDC value. No need to change it from the stock value.

 

changed the stock to WG forge, is coming to 30psi.

I use 26psi, the problem that comes and 26psi in the rotation above 4500 up to 7000 falls to fixed 21psi.

I have to configure EcuFlash to maintain 26 psi between 4500 to 7000 rmp?

 

Thanks,

You're probably right with the .5% thing, as most of my oscillations are from the sub-obtimal Baseline WGDC, but if I can't get rid of most of it in that, i'll go to smaller BEC values as i don't want to lengthen my correction interval.

On a note related to that... i have the correction interval set to 1, but i'm still not getting that many corrections per second... at least not as many as I had wanted to see.

What is your cycles/sec with the interval on 1?

 

That's what I'm still trying to figure out. Supposedly you supposed to be able to tune out the taper - however, if you reach the limits of the stock hardware (boost solenoid, WG, etc.) then it might not be possible.

 

Hopefully someone can help me understand what may be happening in my case. I just took this log this afternoon.

I'm thinking my taper may be evidence that I still haven't fixed all my boost leaks...


And here is what is in currently in my flash:

 

Did you pressure test? Did you find and fix your leaks? BTW the stock turbo will have taper. The best way I have seen to eliminate taper is an O2 dump. My car is tuned for 24 psi and I taper to 22 psi by 8k rpm. But I have a built head which contributes to taper. Despite my taper, my airflow increases all the way to redline. My point is that boost is not what makes power, airflow is what makes power. As long as airflow increases, you are good.

 

I've never seen someone enter a value larger than 100% in their Base WGDC table. Is your local atmospheric pressure really 13.4 psi!??? If not, your BASE BOOST #1 table is gonna be off. Usually with a boost leak I would suspect higher load values than he is getting,hmm. My guess is the boost pill thingy isn't enough. GM BCS can't be beat.