2009 ISX 15

[Rawze]

What make/model engine?... a CM871 ISX?...

35 psi sounds low for a CM871, even for one set at lower HP ranges. Should be more like 36-37 in a hard pull .. or 38 max.

- And are you sure its the 'smart-torque' feature or other problems?.

By the way, there are about 28+ different ramp and rate limiters within various model ISX engines ... so the boost itself being lower than normal may be something totally unrelated to the smart torque feature. Here is a list of all of them typically found in the engine...
ref: https://rawze.com/forums/showthread.php?...6#pid63796

==============================
== What is the engine ser# (The esn#)?.

== What make/model truck?.

== Do you know what program has been flashed into the ecm?.

== Is it the truck/engine de-mandated (deleted)?.

Mileage, some history, etc.?