P0299 Question - ecodiesel

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08-19-2022
donald7150

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P0299 Question - ecodiesel

I have a question about the Boost control deviation tables. are these the tables used to determine under/overboost conditions?

Attachment 123504 Attachment 123505
10-04-2022
Camaro6

Quote:

Originally Posted by donald7150

I have a question about the Boost control deviation tables. are these the tables used to determine under/overboost conditions?

Attachment 123504 Attachment 123505

Did you ever figure out if that what that parameter is? I'm curious as well.
01-08-2023
donald7150

I did not

Changing those values seems to have no effect on anything

Basically what happened was I bootlegged a tune that someone foolishly posted on this forum from a vendor i wont mention, I foolishly copied all the relevant values into my file and started using it. The truck behaved beautifully aside from cruising at highway speed entering a moderate grade i would get a P0299 underboost and limp mode.

If i floored it at every hill it was absolutely fine (definitely not ideal)

So I returned the stock boost control tables to my tune and all has been well for about 12,000km now and still the full effects of the tune

Boost control tables are just vane position and while they do control the boost, it has to line up with the boost setpoint tables as well. If the vanes are not spinning the turbo enough to reach the target in the boost setpoint table then that may cause the issue. I didnt experiment with it

The tune i have would command the vanes at around 70% at cruising speed/throttle position (im guessing in an effort to gain some MPGs) and i guess wasnt producing the boost pressure the ecu was expecting and threw the code every single time. Stock table has them at 85-90% in that same range. Once i went back to stock on those particular tables the underboost issue was gone

Ive learned alot since the original post and that tune i downloaded was definitely not a good one.
01-25-2023
raceghost

Quote:

Originally Posted by donald7150

I did not

Changing those values seems to have no effect on anything

Basically what happened was I bootlegged a tune that someone foolishly posted on this forum from a vendor i wont mention, I foolishly copied all the relevant values into my file and started using it. The truck behaved beautifully aside from cruising at highway speed entering a moderate grade i would get a P0299 underboost and limp mode.

If i floored it at every hill it was absolutely fine (definitely not ideal)

So I returned the stock boost control tables to my tune and all has been well for about 12,000km now and still the full effects of the tune

Boost control tables are just vane position and while they do control the boost, it has to line up with the boost setpoint tables as well. If the vanes are not spinning the turbo enough to reach the target in the boost setpoint table then that may cause the issue. I didnt experiment with it

The tune i have would command the vanes at around 70% at cruising speed/throttle position (im guessing in an effort to gain some MPGs) and i guess wasnt producing the boost pressure the ecu was expecting and threw the code every single time. Stock table has them at 85-90% in that same range. Once i went back to stock on those particular tables the underboost issue was gone

Ive learned alot since the original post and that tune i downloaded was definitely not a good one.

Um you missed some data copying within that foolish posted tune. There are some underboost/overboost trigger messages hidden in plain view within the rom. Goodluck.