'07 LMM Express Van Commanded vs Actual boost, etc.

[Jonny Digital]

First off, I am new to diesel (and EFI live for that matter). I have tuned many gas/ethanol vehicles for a multitude of modifications, I know much less about diesel at this point.

I took on a job recently of tuning a 2007 Express 3500 w/LMM. I got the thing running quite well, good power and the transmission is holding up pretty well! I was trying to log vitals with the scan tool, but it seems like the numbers are a little weird? I logged commanded map and map, when WOT the commanded shows 317kpa while the pressure is hitting 363kpa (About 6psi higher than I wanted). Am I missing something? At first I thought it was a spike, but its sustains this boost level the whole time. I know the LMM is a little weird in controlling boost (at least from what I've read) and I was going to mess with the vane position to see if that helps the situation. Anything else I should be looking for? What PID's should I be logging? I see people talk about GM.BOOST2_DMA but I don't have that as an option as far as I can tell...

Thanks for any insight you can give!

Also, I read that they were planning on converting the Express van OS to DSP5 and I don't see it as an option, is this going to be supported (or is it silently being supported right now)?

[TDFDiesel]

To convert to DSP5, you have to go to the convert tab. Convert to DSP5 OS, save, close everything out and re-open. (This is from memory, so I might of missed a small step.) Once you re-open you should have under the custom calibration menu's for your DSP1-4 positions.

On the data logging, which PID List are you using? I personally use Duramax LBZ Imperial for an LMM.

[lotsofmiles]

First off, I am new to diesel (and EFI live for that matter). I have tuned many gas/ethanol vehicles for a multitude of modifications, I know much less about diesel at this point.

I took on a job recently of tuning a 2007 Express 3500 w/LMM. I got the thing running quite well, good power and the transmission is holding up pretty well! I was trying to log vitals with the scan tool, but it seems like the numbers are a little weird? I logged commanded map and map, when WOT the commanded shows 317kpa while the pressure is hitting 363kpa (About 6psi higher than I wanted). Am I missing something? At first I thought it was a spike, but its sustains this boost level the whole time. I know the LMM is a little weird in controlling boost (at least from what I've read) and I was going to mess with the vane position to see if that helps the situation. Anything else I should be looking for? What PID's should I be logging? I see people talk about GM.BOOST2_DMA but I don't have that as an option as far as I can tell...

Thanks for any insight you can give!

Also, I read that they were planning on converting the Express van OS to DSP5 and I don't see it as an option, is this going to be supported (or is it silently being supported right now)?


last I knew Cindy told me no DSP5 for the vans - major Fail :(