LNF PID Tables

[hockeymandan2828]

Think it could be that I am possibly using a GMPP stage 1 tune vs stock tune as a base?

[codename Bil Doe]

From what everyone else has said the GMPP has more limiters. If anything, you should be having problems boosting and not this part throttle to full instant boost issue.

[hockeymandan2828]

Log from this morning after I checked wiring and swapped sensors (MAP to charge pipe).

10-7-14 drive to work.hpl

[hockeymandan2828]

And tune..

09-24-14 93 Oct - No Otitq.hpt

[cobaltssoverbooster]

gmpp spools turbo hard around 3/4 throttle. in th epast we believed it had to do with the calibration of pedal and tb delay time. tb delay time is pretty high from the factory but it seems it may have been raised for gmpp due to the higher boost levels. they would pre-set a higher delay value as a safety to prevent slamming full boost at the drop of the hammer(keep it soft and limit kr which we are prone to). the delay period would have been raised around 95-100% throttle, then mid range which was probably not changed much, would be left prone to violent spooling at partial throttle. unfortunately tb delay time is not accessible at this current time.
the effects can be limited through proper calibration which you are being walked through but to be-rid of the issue entirely will be hard. Pid tables are key to this and i believe you are in the proper section of this forum to get it dialed in to your liking.

i have a feeling gm was all too excited about this motor and failed to properly calibrate the knock sensors for each particular chassis style. because of this, the ecu used would have to combat a wide range off knock prone scenarios. failing calibration on such a device would lead to bandaid safety fixes in tuning with results mimicking what we have seen in the past, now present today in this thread again. This is why in feature request i have filed for answers on adding KR Calibration to these ecu's. it has the potential to fix a wide range of errors we have now.

[codename Bil Doe]

Good info. Here's where we stand now. We were able to eliminate the knock problems. The issues are in the transition range 21-22% pedal. The transition spot is the same as every LNF I've seen. The issue is uncontrollable boost request once you hit that 21-22% pedal threshold. This occurs at any RPM. ECU wants full boost. He is running slightly milder OS tables than I run on street cars and my race cars. Other changes tried included drop the OS tables way low (to the point that it shouldn't have reached full boost even at 6k rpm), lowered the prop gain tables which should have had same effect.

I'm still thinking a hardware issue. He just found a log in which this still occurred before he ever touched the PID's, OS, OT, or anything else. Could it be GMPP related? I've never seen it before and have scoured every single table. Knowing that it happened before he ever touched the tables points to hardware or previous tune/mod.

[ericemir]

Good info. Here's where we stand now. We were able to eliminate the knock problems. The issues are in the transition range 21-22% pedal. The transition spot is the same as every LNF I've seen. The issue is uncontrollable boost request once you hit that 21-22% pedal threshold. This occurs at any RPM. ECU wants full boost. He is running slightly milder OS tables than I run on street cars and my race cars. Other changes tried included drop the OS tables way low (to the point that it shouldn't have reached full boost even at 6k rpm), lowered the prop gain tables which should have had same effect.

I'm still thinking a hardware issue. He just found a log in which this still occurred before he ever touched the PID's, OS, OT, or anything else. Could it be GMPP related? I've never seen it before and have scoured every single table. Knowing that it happened before he ever touched the tables points to hardware or previous tune/mod.

Eliminate the KR problem... please dive into this a little....

[cobaltssoverbooster]

it is very possible a hardware issue is causing these issues. as you well know there are not just knock sensor tables missing. TB calibration is missing as well. There is no way to fine tune the size, the gains for the stepper motor, and the delay as for-mentioned in previous post. the computer OS is very very odd at the least.
it is possible that with 20% being not only an off idle throttle zone but a cruise zone the computer can make power one of two ways and changes its methods at a threshold value that ends up extremely close to 19-24% tps. One method would be control power by adjusting the TB plate solo. the other method would be to control the WG signal and up the boost without moving the plate much. after a certain point the TB hits wide open and then boost is the only way the computer controls power output (aside from the obvious spark and cam shifts). the threshold controls could very well be similar to say, ve and maf table blending for speed density vehicles. you run the TB all the time (like a ve table is the base fueling reference) but on top of that we decide we want to add boost control (like maf being enabled to correct short term, rapid airflow errors). set the boost control activation too low and you get erratic low pedal position/low load boost control. Raise it higher and let the TB be the solo controller for a zone that should be all motor anyways, and the boost errors become a thing of the past as that zone would be basically deactivated. In speed density you can turn the maf blend on at 100 rpm or 10,000 rpm, but blending its activation point is still a mystery to some people. you find that sweet spot and its like night and day for street drive ability. Could be the same with TB operation modes.

i have an idea as to how its working based off of the common occurrence the forum has been trending over the years. my only issue is that i am having a very hard time finding the proper way to word it in an understandable fashion. i try to make it easy to understand but every time i re-read my post preview i find i'm missing the correct wording on a few functions that would throw almost anyone off, thus ruining the posts informative flow. equally as frustrating, is not having an lnf to test newer theories and custom parts with.

[codename Bil Doe]

What I've found is that the tb position, timing, and boost (wgdc) are all related. That's why I've been saying that having a 1:1 relationship between pedal and tb is not important.

Current problem is why his car is doing this when no one else's is with identical or more aggressive tunes than what he is running.

[codename Bil Doe]

Eliminate the KR problem... please dive into this a little....

ALL tables must be smooth with no sharp transitions, MAF must be dialed in. "KR" is a default for any condition that the ecu does not like. Also, Burst Knock table shouldn't be zeroed with aggressive boost levels and ramping. Even a minor value here will help tip in events.

[cobaltssoverbooster]

What I've found is that the tb position, timing, and boost (wgdc) are all related. That's why I've been saying that having a 1:1 relationship between pedal and tb is not important.

Current problem is why his car is doing this when no one else's is with identical or more aggressive tunes than what he is running.

seems i missed your question previously. Does the TB shaft have any play? Does the pedal sensor record a smooth sweep with no drops or spikes when moved slow or fast at KOEO scanning? TB Position sweep same test?

[codename Bil Doe]

hockeyman would have to answer that. But, 21-22% is the correct transition point. So, I don't believe that's an issue.

[hockeymandan2828]

So, long story short I re flashed my car with my stock tune. Changed the car to accept the 3 bar map and the fact that i have no cat. Viola, the car is stock slow but runs like a dream. Log and tune attached.

This means that my GXP has been running wrong for a solid 1.5 years, aka ever since I got my tune from the "expert tuners". Yippie, time to re-tune everything.

10-9-14 drive home.hpl
Stock 2007 GXP - 3bar.hpt

[cobaltssoverbooster]

file corruption

[hockeymandan2828]

Wait, do you mean the tunes I just posted were corrupt, or my the problems I was having were due to file corruption.

[cobaltssoverbooster]

your stuff sounds like its been corrupt from the start. reverting to your old factory tune with no errors was the dead give away

[hockeymandan2828]

Thats what I thought you meant.. Good deal. Well, time to re-tune!

This really does explain a lot though. For example, my spark maps NEVER wanted to act correct no matter what I did with the opti spark tables or the regular tables. There was a time where I had 21 deg advance in the regular tables and a opti spark of +25, and it would go to 10 deg advance max. so annoying.

[cobaltssoverbooster]

this happens more frequently when flashing after letting the vehicle sit overnight and without a charger on the battery during flashing.

[hockeymandan2828]

interesting.. However, thhat would mean that it happened every time I flashed the car because it drove like this for over a year and a half, with me flashing it a lot.

[cobaltssoverbooster]

if anything it could only make it progressively worse every time. it isnt a guarantee that there will be a flash error every time. it is only more prone to it at lower voltage situations.