Having trouble getting the vane position set with my new turbo

[GetBoosted]

Hello,

I have a 2006 Silverado w/ the LBZ duramax and recently installed a slightly larger turbo (went to a Danville Stage 2 GT3794va) and I'm having trouble dialing in the vane position so I can get the turbo to spool faster and rid myself of the P0299A (low boost) code I am getting. I've been working within the B2214, B2212, and B2210 tables and it seems that no matter what I put into these tables, the turbo is not honoring the requested vane position.

The only other part of the tune I have modified so far is to disable the EGR system.

My mods are:
* Danville GT3794va
* 3" MBRP downpipe
* 4" MBRP exhaust
* EGR block off plate

Am I missing something or is there something else I must do?

Thanks!

Chris

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Also, the data log can be found at https://www.dropbox.com/s/6lp5gqer2vsp1sp/E35_0024.xlsx (wouldn't let me attach it to the post)

[Mitco39]

Have you looked at your Max position tables for the vane position?

[GetBoosted]

Have you looked at your Max position tables for the vane position?

I checked over the cold start but that's a good point since I didn't really check over the other tables. I've attached them for reference. My assumption was that since it's happening when I am warming up the truck that I should focus on the cold start for the max position but perhaps that's not an accurate assumption.

I'll have to go through these tables and set them higher to reflect the max position I currently have in the other tables. Is there any rule of thumb for setting the max on top of what I'd like the value to be?

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[Boost]

LOL 299 has been kicking my ass for 2 weeks on some LMMs since the latest update (I am not blaming it!!!). I am about to start a thread on it.

[GetBoosted]

LOL 299 has been kicking my ass for 2 weeks on some LMMs since the latest update (I am not blaming it!!!). I am about to start a thread on it.

I hear ya. That other set of PIDs looks to be the ticket to why I wasn't able to get the vanes to stay closed longer. I took the tune back to square one and then applied some isolated changes to those tables (and I up'd some portions of the vane position maps by 15%) and while it still needs work, it certainly solves that issue. The boost is still laggy but I'm guessing I'm going to need to turn my attention to timing or something else at this point.

Thoughts? Should I continue fooling with vane position or should I retard timing before I hit boost to get the spool to improve?

17037

[asmithIII]

Try letting PCM control vane position and boost

Turbo boost control fuel enable
Turbo boost control fuel disable

Once PCM has control, boost is matched to fuel flow using...

Main injection mixture limit

Enabled at rpm greater than 600

Hope this is helpful

[Mitco39]

This might sound weird but with P0299 try turning off the AC circuit DTC P0532/P0532 and see if your low boost goes away. You might be surprised :)

[GetBoosted]

Try letting PCM control vane position and boost

Turbo boost control fuel enable
Turbo boost control fuel disable

Once PCM has control, boost is matched to fuel flow using...

Main injection mixture limit

Enabled at rpm greater than 600

Hope this is helpful

Thanks for the insight. I totally missed those. I reverted all my changes except disabling the EGR stuff and applied changes to those tables (B2231 & B2232) and I've attached the results. Keep in mind this log was right after I wrote the tune to the truck so it's on a cold truck but that is typically when it's easiest to replicate the code coming up and I wanted to try it out so I was antsy :-).

Throughout the map there is normally around a 2 psi difference between desired boost & actual boost which is weird so I'm not sure why that's happening. Other than that, it looks like the requested boost starts to get away from the actual as I start to put my foot into it (around 3/4 of the way through the chart). The code didn't come back yet so I'm going to take another logging run in the morning to check again and actually let the truck warm up this time. Thanks again.

I'm thinking that I may need to combine this change with the update to the max vane position to help out the spool but I'll report back after I get to do more logs tomorrow.

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This might sound weird but with P0299 try turning off the AC circuit DTC P0532/P0532 and see if your low boost goes away. You might be surprised :)

Thanks for the info. I haven't had to use the A/C lately since it's been awesome weather (70 degrees and sunny) but I can give that a look for sure.

[asmithIII]

Main injection mixture limit lets the PCM use MAF and fuel delivery to determine the correct boost.

Very useful, once enabled. Allows fine tuning of EGT.

[GetBoosted]

Main injection mixture limit lets the PCM use MAF and fuel delivery to determine the correct boost.

Very useful, once enabled. Allows fine tuning of EGT.

Are you thinking that I need to richen it up a bit to get the EGTs a little higher to get the turbo moving or are you thinking what I have now (stock) is fine for that?

Here's what my tables look like currently (NOTE: B0795 hasn't been modified but I wanted to give as a reference):
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Also for reference, this is what B2231/32 looked like prior to me updating them:
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Thanks again for the help!

[asmithIII]

Seems that parameters above mixture limit should be changed to 600 rpm, not 6000. Also, until fuel flow goes above enable rpm and flow, turbo vane position will be set according to vane position tables. Might want to increase max allowed vane setting at low rpms and decrease desired boost pressure.

The stock turbo has trouble making boost under low rpm and low load conditions. Table of desired boost can not be very much higher than atmospheric pressure. Larger turbo might have even more trouble keeping up with some number in a boost table. That why PCM needs to be enabled to control vane position sooner than before.

No need to richen mixture. Adjust mixture later after things work.

[rcr1978]

This might sound weird but with P0299 try turning off the AC circuit DTC P0532/P0532 and see if your low boost goes away. You might be surprised :)

Is there a interesting story behind this one?

[GetBoosted]

Seems that parameters above mixture limit should be changed to 600 rpm, not 6000. Also, until fuel flow goes above enable rpm and flow, turbo vane position will be set according to vane position tables. Might want to increase max allowed vane setting at low rpms and decrease desired boost pressure.

The stock turbo has trouble making boost under low rpm and low load conditions. Table of desired boost can not be very much higher than atmospheric pressure. Larger turbo might have even more trouble keeping up with some number in a boost table. That why PCM needs to be enabled to control vane position sooner than before.

No need to richen mixture. Adjust mixture later after things work.

Ok thanks for the details. I'm not sure why it's set to 6k RPM for the Main Injection Mixture Limit RPM Param... I validated against my stock file and that's where it is set in that one too which was a direct pull off the ECU. I will update it to see if I can get it to start honoring those tables and also up the max vane position as well. After that, I will down the expected boost a bit to keep them in line if it doesn't work.

Code came back btw. Logs looked the same as I previously posted too... just seems the requested boost gets away from actual.

[asmithIII]

Try pasting high altitude boost in low altitude table. That is only a temporary fix, good only during light loads

Either boost level comes from some value in a table or boost is calculated from MAF and fuel deliver by fuel air mixture table.

Just trying to get ECM to control boost for you. Must be enabled first.

Also, with the ECM controlling boost/vane position, table B2252 might need some adjustment. Overall gain might need an increase when desired boost becomes greater than actual boost. The low boost areas have already been logged. Need to close the larger turbo more than the stock turbo by increasing the gain in the P.I.D. Stock program has a large area of low gain around 1200 rpm and 60 mm fuel. Those levels might need to be increased. All levels might need some increase in gain.

I'm not sure why the level is 6000rpm either. Seems that the stock engine program was designed by a committee.

[asmithIII]

After some logging, found that desired and actual boost seldom agree with the ECM controlling the boost

When ECM control is enabled, boost is calculated from mixture table. If ECM control is not enabled, then boost values come from a table and should be what you were looking for. Desired boost should agree with actual boost much more closely.

Afraid that my method for controlling boost would seldom have actual agreeing with desired. My method is useful in controlling EGT.

[Mitco39]

Is there a interesting story behind this one?

Just a lot of head scratching and trying different things. The issue arises I believe if you are not using the right 8594 setup. Same OS's for different years in some cases are not the same. The LMMs are a bit quirky but nothing compared to these LMLs, argh. It only gets worse. haha