So I’m having trouble with my truck cranking but not starting. 03 Silverado 5.3 P59 ECU running on tune file that’s for the cam I installed years ago. I installed an EFISource LS1 style 3 Bar MAP sensor in my truck manifold and I know the truck is still on a MAF tune.

I’m seeing where you need to get to the original tune file, tune for the 3 Bar MAP and then tune from there on the original file vs making changes to the current modified file. The problem there is, unless there’s a way of resetting the ECU back to factory, I’m not sure how to access the stock file since my tuner that originally did the work doesn’t tune anymore.

Once I get over that hurdle, I then have to figure out how to turn off the MAF and find a good wideband kit and install that I’m assuming? I know I’ll have to install it in the down pipe (actually going to shoot straight out the fender off my S475).

 

You can go to the hp tuners tune repository and find a stock tune. Or just spend the credits to go to a speed density op.

 

I believe Matt from sloppy mechanics may have some YouTube videos on the subject.

 

Converting OS no longer costs credits. Which is nice.
Stock file from the tune repository.
Open it, save it to a new name, change only the OS, save it, close it, reopen it, Burn the ecu(make sure you write entire and not just calibration. The pop up box will say in red letters "Brickable") Turn the key off, turn the key on, open scanner, connect to truck, right click on an open space and "add channel" I believe its Engine_General_manifold_Manifold absolute pressure, 3Bar. MAKE SURE THE PARAMETER SAYS 3 BAR> Click on it. Close the channel window and hit the red log button. Verify your map reading is accurate by making sure its the same as the current BARO in your area. Should be around 100. If the nits are in PSI or INHG you can right click when not logging and change them to KPA. If all that checks, you are now 3bar OS Now you will need to repop your VE table and scale it to 3 bar, disable maf, change injector data yadda yadda. After all that you can flash the ecu using write calibration only and unless you mangled something or there is a physical problem with iring or mechanical parts, the truck should make hot water.

I can't remember off the top of my head if the P59 reopens after the OS change with two VE tables (one that goes from 0-105 and one that goes from 105 to 305) Or like the PO1's opens with one table all the way out to 3 bar, but in either case, I use the my original VE table that was scaled to 105 and reuse it up to 105 (if you have two tables, make sure the second table that goes from 105 to 305 also has the same values in the 105 row). Then I copy and paste the same 105 values into the 305 row. Then I will multiply the new 305 row by like 35%. Click and drag the entire table and use the "Interpolate between horizontal boundaries" button above the table. I believe its the one on the left. This will populate your entire VE table all the way up to 305 KPA. You will need to do this to start as the VE tables repopulate after the 3 bar OS change to the default high (which I think is 1.47 if I remember right)

Good luck

 

Great info. No credits is nice.