3 bar map sensor trouble

[aruss99]

Hi all,

Recently finished my turbo ls build, with no major issues except for the map sensor. The motor is a 2003 lm7 5.3l with 80lb injectors. It runs just fine with the stock map sensor, but when I convert to a custom os, (3 bar speed density) the map sensor reads either way high, or way low. (0 kpa at key on, 314kpa when running.) The motor will run for a little bit, then dies. I have gotten it to read correctly once, let it idle up to temperature as it should, shut it down, and the next day, without changing anything, the truck wouldn't even start. I am at a loss as to what to do because all the forum threads I have read have said the only changes necessary is changing the linear offset and the scaling of the map sensor... I have a log of the motor trying to start as well as my 3bar tune. (the IAT sensor was unplugged in the data log, but having it plugged in makes no difference to the results I am having) if anyone has any suggestions on things to try that would be very much appreciated... this is the second 3 bar map sensor I have gotten, so I am confident it is not an issue with the sensor itself.

Link to tune and log files https://drive.google.com/open?id=0B1...mROVDNBTU9SNU0

Thanks