Optimized Idle - OI Target Engine RPM Too High

2001 Freightliner Columbia DDEC IV:

• My Optimized Idle Engine runs at 1100 RPM.
• I would like to lower it to around 800.
• A few shops have plugged in and tell me that OI RPM is hard coded and no way to change it.

History: I replaced the ECM a few years ago and the new one had generic programming, and OI was not enabled. Long story short, when the shop enabled it, I remember the tech saying aloud, lets bump the RPM to 1100, it will be good for the engine and oil flow. Now the same shop tech says that parameter is grayed out and he cannot change it.

I have been reading the OI service manual, and it says there are customer accessible parameters to have "OI Target Engine RPM ae 0, ae1, ae2, ae3 and ae4". (see attached screenshot)

• How do I set these default targets?
• Per the manual they are supposedly set to default 1000 RPM.
• I would be happy if I could only change ae2 and ae3 to 800 RPM.
  

 

If I turn off OI and bump my Variable Idle, my engine idles all night long, and I do not want that.

OI turns the engine off and on automatically, when cab temperature goes above or below set variance.