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Don Z
May 16th, 2017, 01:32 AM
I am under the impression that the non running BP sensor reading and the MAP sensor reading should be very close. My BP sensor typically reads around 99 kpa and that ties up well with a 29.3 Hg barometer reading that we are currently observing. The MAP sensor is reading 84 kpa. Is there some kind of offset built into this reading?

Thanks,

Don Z

kidturbo
May 20th, 2017, 12:04 AM
The E35 ECM's have 2 possible MAP pids. SAE.MAP and GM.BOOST2_DMA or MAP2. The SAE.MAP reading are not correct, I verified this on the bench. Details at: http://www.duramaxdiesels.com/forum/showthread.php?t=70615

Guessing this might be your issue.

Don Z
May 20th, 2017, 01:52 AM
The E35 ECM's have 2 possible MAP pids. SAE.MAP and GM.BOOST2_DMA or MAP2. The SAE.MAP reading are not correct, I verified this on the bench. Details at: http://www.duramaxdiesels.com/forum/showthread.php?t=70615

Guessing this might be your issue.

Thanks for the reminder. I had noticed the two different PID's when I did my initial look. I will map the two together for a while on the bench with a pressure regulator till I figure out how they couple up with the tables I want to tweak.

I have done a little LB7 towing and mileage stuff for my race car hauler. I just got started on the same thing for an LBZ truck I use to pull my work gooseneck trailers. There is a lot more going on in the LBZ files, but having better control of when and how hard the turbo comes in really seems to help the mileage.

Thanks again,

Don Z