{C0801} & {C0803} Boost

[FUBAR]

Can someone please explain to me how these two voltages are in reference to boost? I am getting a P0299 Underboost code, and for the time being I rasied {C0806} up to 20 seconds to fix it and scaled down some boost tables. But I would like to know how the voltages tables translate in to boost. If voltage is below min for a certain time or above max then code trips meaning under/over boost and vice-versa. So is MIN translate to low boost and MAX high boost? And what would say .0142 V roughly translate into p.s.i. boost?

Thanks,

Andrew

[FUBAR]

Basically how can I tell "X" amount of boost will trip under/overboost code and how I can I increase that margin.

[Boost]

Hmm, I've looked in SI and the only thing I've found so far is that 299 sets when "The measured MAP pressure is more than 39 kPa below the expected range for 10 seconds". Did not mention anything about voltage. Maybe a bad map sensor?

[Boost]

Or you may have to do a Turbocharger learn. Just guessing though...

[FUBAR]

"The measured MAP pressure is more than 39 kPa below the expected range

Where did you find that? Under the page of where it shows MIN/MAX voltage settings, error time, and under/over boost delay time, I cannot find that. What {CXXXX} is that?

And what do you mean by, do a "Turbocharger learn?"

Thank you for the help.

[FUBAR]

This is the best I can find in the Tune tool. The kPa value your speaking of is exactly what I'm looking for.

[Boost]

I am looking in GM Service Information for general info on what would typically set the P0299. I was hoping that the diagnostic flow chart would include some kind of voltage values but it does not.

[Boost]

Sure, my pleasure. We all learn in the process. Is this a LBZ or LMM (info probably the same anyway)? A Turbocharger Learn is something that needs to be performed to prevent a possible P0299 from setting after TC vane position control solenoid valve replacement, TC vane position sensor replacement, ECM replacement, TC replacement, Any service that disturbs the TC components. It's done with a scan tool, not sure if the Flashscan can do it or not. But I am not sure that is your issue. And how are you converting the kPa to voltage?

[FUBAR]

LBZ. And thanks for the info. And I am not converting kPa to voltage. The only thing I got to go off of or find in the Scan Tool is what you see in the pic I posted. I wish I could find where you found "39kPa for 10 seconds" in the scan tool so I could change the "39kPa" value. Up until you told me that, it would do me no good to data log the truck for boost concerns. Since you told me a difference in 39kPa (5psi) in boost will send a flag up,
I can now data log the truck, find out where Actual boost is not meeting Desired boost levels by 39kPa, and correct the problem via mechanically, or tune wise. I just want to find where you found the 39kPa value so I can verify and adjust on my truck.

Thank you so much for the help!

[Boost]

No problem I really enjoy learning about all this and if it helps you out GREAT! I am not looking in the scan tool, rather I am at the dealer working and looking at the diagnostic process for the code. And the info was for an '07 LMM, I'll check in a second if there are any differences between the Classic, and also post a little more info since it seems to be helping you out a little.