Big problem with EFILive

[Black6spdZ]

I want to change the title of this thread and continue discussion about advanced tuning.. ie proper vane position, boost and fueling for optimum EQ ratio

[Tordne]

I sent your info from yesterday to Ross to have a look over. You've given a better explanation here than in the emails so I'm just going to send him a link to this thread in a second.

[Black6spdZ]

Thanks Tordne.. I really dont know how to explain what's happening here. I've thought about working an a non-dsp tune to see if the problem persists. I'm sure most problems are users "tuning" issues, but to have a particular tune commanding from an EGR ON and OFF table simultaneously is beyond me.

[GMPX]

Black6spdZ, when you say you were using the largest base tune, do you mean the non DSP tables?
It's not a problem that has been reported before (well, not that I am aware of). As a controlled test, set all cells in your EGR On tables to 20% and EGR Off tables to 40%, take the environmental factors out (zero B2228 & B2230) and relog. It's sometimes hard to pick where the ECM is looking when a table has 'normal' figures that are also affected by other multipliers. It's quite rare to ever see the 'exact' value from a table shown as the final figure in the scantool.
We do have a term around here "It's a Boschism", comes from the fact Bosch ECM's just seem to do weird things.

[bballer182]

I'll try here as a last resort since I cant get an answer to this issue anywhere else. There shouldn't be any combination of parameters commanding EGR ON in this tune yet going back over a log the ECM is using the EGR ON vane position table although it was for sure using the EGR OFF commanded Boost table.. I had to go over it a few times just to be sure but thats exactly what it is doing.. been trying to track down a P0299 code all night at the track and making changes to the EGR off vane table and all along it has been using the ON.. what gives? Is this some kind of EFILive bug? Here are the values used in this tune. BTW, I was using the largest "base" tune and all EGR hardware is gone. This is an LMM OS 52628594. Just so I can prove the point further I've made a couple screen caps.. one is the log and the egr ON table on left, and OFF table on the right. take a close look at the actual and desired vane % compared to the lookup on the two tables. Second is the log on the same frame, egr ON desired boost table on the left and egr OFF on the right. You can clearly see on the log the desired boost is being pulled from the egr OFF table exactly as it should!


Dude, start by setting B1501 to disable, then raise all you MIN temps to the max upper limit allowed. (B1503, B1520, B1521, B1522, B1523). Just by leaving those the way they are you are setting the ECM into a conflicting circumstance. And second i'm assuming you have but... Have you logged the EGR to see whether it is in operation or not or are you taking that for granted?



Black6spdZ, when you say you were using the largest base tune, do you mean the non DSP tables?
It's not a problem that has been reported before (well, not that I am aware of). As a controlled test, set all cells in your EGR On tables to 20% and EGR Off tables to 40%, take the environmental factors out (zero B2228 & B2230) and relog. It's sometimes hard to pick where the ECM is looking when a table has 'normal' figures that are also affected by other multipliers. It's quite rare to ever see the 'exact' value from a table shown as the final figure in the scantool.
We do have a term around here "It's a Boschism", comes from the fact Bosch ECM's just seem to do weird things.

Boschisms... Yes... :throw::doh2:

And while performing this test set B2231 and B2232 to the max upper limit so that the ECM uses the vane tables instead of the the boost tables.

[JoshH]

Two things I see.

1. Based on what is visible in your screenshots, I see nothing that suggests the tune is running on the EGR off vane tables.

2. You are running a lot of boost for a stock turbo (assuming this is still a stock turbo).

[Black6spdZ]

Two things I see.

1. Based on what is visible in your screenshots, I see nothing that suggests the tune is running on the EGR off vane tables.

2. You are running a lot of boost for a stock turbo (assuming this is still a stock turbo).

1. Correct, it should be using the off tables but seems to be referencing the On instead,
2. Its a 4094 turbo

Could any of this be caused by lack of egr hardware? Would something need to be added to simulate the egr position? I'm guessing its a var. resistance?

[ScarabEpic22]

Dont know much about the Dmax, but Im with bballer on this one, looks like the ECM is getting confused and defaulting to the EGR on tables. But Im not sure you've actually disabled the EGR in the tune either...

[Black6spdZ]

If that is the case the descriptions of those EGT functions are a little misleading. B1503: coolant temp must be above this value before the EGR system will be allowed to function. I set it at Max knowing the coolant temp will never reach that value... and so on with rest of the parameters. Please correct me where I am wrong.

Sent from my G2X

[JoshH]

If you look at the tables bballer mentioned at the end of his post, you'll see the target vane tables aren't always used. Once the fuel quantity goes over the value in those tables, it uses the desired boost tables and makes the vanes do whatever it can to achieve the desired boost. In that case it is limited by the max and min vane position tables.

[bballer182]

Josh is 100% correct. I should have clarified what those tables are used for.

Oh and just for good measure. zero out B1526, B1527, B1528 (desired flow)

[Black6spdZ]

11263

How does this look?
All EGR tables are zeroed. Ok.. I think I may have tracked down the issue with everyone's help here.. just go ahead and shoot me now. I'll just say this isn't my original tune BUT I should have caught it sooner.. it just so happened that EGR Max table is very close to the EGR on table... ooops.. sorry for chasing some tails. :( Just a bit of info.. a 4094 seems to max at about 40 PSI with 27% vane position. Not that this turbo is expected to be linear.. but would I be correct in assuming that a target of about 45 PSI "12% increase" would need to be aplied to the vane as well 27% * 12% = ~30% new vane position?

[bballer182]

In trying to tune a new turbo that IS VGT, let the ECM tune it for you. Set B2231 and B2232 to zero and let the ECM find the vane position for the requested boost. log it then apply the logged vane position back into the tune. and repeat. And you missed it again with the EGR, read my post again and adjust your tables that i said.

[Black6spdZ]

B1520 "EGR will be disabled if the intake temperature is below this value." Wouldn't we want this value high? If you zero B2231 and 32 would the vane table be necessary? I've made a map in EFI scan, mm3 vs vane% vs boost to plot the boost levels at each vane position. I've run all of the logs through it and an interesting pattern shows.. about 25-27% produces the most boost, either side and it starts to drop. So far max has been 363kPa "@ sea level" and this is with 2360uS "60% injectors".

[bballer182]

B1520 "EGR will be disabled if the intake temperature is below this value." Wouldn't we want this value high? If you zero B2231 and 32 would the vane table be necessary? I've made a map in EFI scan, mm3 vs vane% vs boost to plot the boost levels at each vane position. I've run all of the logs through it and an interesting pattern shows.. about 25-27% produces the most boost, either side and it starts to drop. So far max has been 363kPa "@ sea level" and this is with 2360uS "60% injectors".

Thats not exactly the best way to go about interpreting the data. As i'm sure you know MM3 is an arbitrary number and means nothing in even a stock tune let alone and modded tune with 60% over injectors. The map that you should make is a map that has the same data and axis as the vane position table. and take into account BARO/altitude. if you are pretty close to sea level don't worry about it.

With regards to the vane tables being necessary with B2232 and B2231 disabling vane referencing; the vane tables are used like quick reference tables when changing fueling rates while driving. romp on the skinny pedal and the ECM looks up the desired vane position for the commanded fuel and moves the vanes there quickly to attain the boost you want. leaving the vane referencing off or poorly tuned will result in the ECM having to find the correct position after it has discovered that the number in the vane table is wrong, equaling turbo lag.


Dude, start by setting B1501 to disable, then raise all you MIN temps to the max upper limit allowed. (B1503, B1521, B1522, B1523) lower B1520. Just by leaving those the way they are you are setting the ECM into a conflicting circumstance. And second i'm assuming you have but... Have you logged the EGR to see whether it is in operation or not or are you taking that for granted?

Yes, that is correct. I'll edit the OP for correct info.

[Black6spdZ]

here is my proposed vane table based on all my past logs, averaged actual vane position on them all and smoothed a little. any thoughts?

[Black6spdZ]

and here is the corresponding boost table created using the same log and averaging process.

[bballer182]

I find that red spot there in the middle a little interesting, seems a little tight for the boost it should be producing. If you have plugged in data from a log onto the vane table you must have smoothed it WAY out...

[Black6spdZ]

maybe the ecm is having to tighten the vanes up alot to get the 4094 to spool with part throttle acceleration?

[Black6spdZ]

In trying to tune a new turbo that IS VGT, let the ECM tune it for you. Set B2231 and B2232 to zero and let the ECM find the vane position for the requested boost. log it then apply the logged vane position back into the tune. and repeat. And you missed it again with the EGR, read my post again and adjust your tables that i said.

I started to do this on my own vehicle, stock LBZ.. and then I noticed that the actual vane % was higher than the lookup table. ECM is applying the IAT vane table to the final result that I am logging.. well crap. I don't want to do a hack job of a tune and zero the IAT vane adjustment table or multipliers.. GM added these for a good reason, air inlet temp and coolant "engine" temp have a major effect on diesel combustion. So fancy me this, how in the world can I apply those calculations on my loged vane position map and get a correct map? I thought about building an excel spreadsheet to do this but I would have to make a generalized assumption of the IAT.. it changes too much to make an accurate map. Can a calculated PID be made to lookup other table values?

[bballer182]

That's exactly what i did. I built a huge spread sheet that took me almost 2 weeks to complete that calculated my boost based on actual fuel delivered and then modified my vane tables to match. And something to keep in my is that the ECM is not using the vane tables to make boost pressure once you get above X RPM and X fuel (B2232 and B2231) so the IAT and ECT vane modifiers are really all that important.

[andrewjamesbond1]

That's exactly what i did. I built a huge spread sheet that took me almost 2 weeks to complete that calculated my boost based on actual fuel delivered and then modified my vane tables to match. And something to keep in my is that the ECM is not using the vane tables to make boost pressure once you get above X RPM and X fuel (B2232 and B2231) so the IAT and ECT vane modifiers are really all that important.

Did you mean to say "are not all that important"?

I am trying to dial in my turbo as well and wanted to make sure that I didn't have to do anything special. Thanks bballer!

[Black6spdZ]

This is the first forum I've come to where people will actually talk and share info on REALLY tuning.. not just throwing fuel into the motor and making it faster.. I like a smooth linear acceleration if I hold the pedal in one position.. not hit a hot spot and boil the tires down. I spent a couple hours last night making an IAT adjustment spreadsheet.. in the end really didn't change much. So how do you go about calculating optimal boost? My first thoughts would be to take the factory Main Injector Mixture Limit table B0795, richen it a bit then use that as a base to calculate the boost. I've found this bit of info searching the subject:

"Diesel fuel is less volatile and is effectively burned as it is injected, leaving less time for evaporation and mixing. Thus, it would form soot (black smoke) at stoichiometric ratio.

Best power/econ should be near 0.6....60% of the stoichiometric fuel quantity for each air rate.

0.6 EQ is 1.66 lambda or an air fuel ratio of 24.5...slightly lean."

As it sits now the lambda at low loads is ~0.9 , isn't that rich? ~14:1, and then they lean it out on the upper end.. but 1.3 is still richer than the proposed 1.6 lambda that someone suggested is optimal.. hmm not sure what's best.

[andrewjamesbond1]

Might be. That extra fuel will create heat needed to spool up the turbo quicker. I am nowhere near an expert, but that's why it might be richer than the optimal lambda. Now is that too rich? I have no clue, need to talk to the experts on that one. And who knows, I could be totally wrong, someone please correct me if that's the case

[andrewjamesbond1]

bballer,

Do the vane position adders play into affect even when boost control is enabled? For example, let's say you are at 1600 rpms, fuel at 40 mm3. Desired boost is 17 psia. (all of this is hypothetical) The corresponding vane position in the vane table is 50% and the IAT adder is 12% at 1x multiplier (It’s cold outside :P). So, you are cruising thru town, give it some pedal and call for 40 mm3 at 1600 rpms. What is the ECM going to command when it comes to vane position when it references the vane tables? Will it say, “Hey, the vane table say 50%, but the adder says 12%, so I am going to command 62% for my vanes and see if I can get 17 psia”??? Or will is say, “vane table is 50%, screw the adders, and let’s see if I can get 17 psia”???
I was curious about this in case when I log and make corrections to my vane tables.

[bballer182]

This is the first forum I've come to where people will actually talk and share info on REALLY tuning.. not just throwing fuel into the motor and making it faster.. I like a smooth linear acceleration if I hold the pedal in one position.. not hit a hot spot and boil the tires down. I spent a couple hours last night making an IAT adjustment spreadsheet.. in the end really didn't change much. So how do you go about calculating optimal boost? My first thoughts would be to take the factory Main Injector Mixture Limit table B0795, richen it a bit then use that as a base to calculate the boost. I've found this bit of info searching the subject:

"Diesel fuel is less volatile and is effectively burned as it is injected, leaving less time for evaporation and mixing. Thus, it would form soot (black smoke) at stoichiometric ratio.

Best power/econ should be near 0.6....60% of the stoichiometric fuel quantity for each air rate.

0.6 EQ is 1.66 lambda or an air fuel ratio of 24.5...slightly lean."

As it sits now the lambda at low loads is ~0.9 , isn't that rich? ~14:1, and then they lean it out on the upper end.. but 1.3 is still richer than the proposed 1.6 lambda that someone suggested is optimal.. hmm not sure what's best.

You are on the correct track of thinking, however, the mixture table (b0795) is only used as a limiter and really is pointless. Max it out to eliminate it as a table of irritation and fine tune your fueling first then take your math you used to calculate the correct amount of air that should be in the each cylinder. B0795 is based on stock fueling assumptions and any modifications to the PW tables throws it off, so it's good just to get rid of it. You have a tough situation because you have over-sized injectors and that makes it harder to calculate actual fuel quantity being injected. Although you can use your eyes and look at the tail pipe. You will know you have a lower EQ (<.65) if there is no visible smoke. it will start to haze around .75 or so. Best EQ for best HP is said to be .9 the best for mileage is .6 - .65


SIDE NOTE: If you can maybe change the title of this thread as the discussion has shifted from being a problem to tuning theory.

[bballer182]

bballer,

Do the vane position adders play into affect even when boost control is enabled? For example, let's say you are at 1600 rpms, fuel at 40 mm3. Desired boost is 17 psia. (all of this is hypothetical) The corresponding vane position in the vane table is 50% and the IAT adder is 12% at 1x multiplier (It’s cold outside :P). So, you are cruising thru town, give it some pedal and call for 40 mm3 at 1600 rpms. What is the ECM going to command when it comes to vane position when it references the vane tables? Will it say, “Hey, the vane table say 50%, but the adder says 12%, so I am going to command 62% for my vanes and see if I can get 17 psia”??? Or will is say, “vane table is 50%, screw the adders, and let’s see if I can get 17 psia”???
I was curious about this in case when I log and make corrections to my vane tables.


If the ECM is "controlling" boost then it will look up the desired vane position plus all multipliers and move to that position. If the ECM finds that the position is not correct then it will hunt and find the correct position. If the ECM is NOT "controlling" boost then it moves to the vane position plus all multipliers and disregards the desired boost number and whatever boost is being produces is it.

[andrewjamesbond1]

So if I want the computer to find the best vane position when controlling boost for quick look up and fast spool times, what do I need to do to the adders to dial it in correctly? Zero them out, log and paste results then re-enable adders?