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Programming changes necessary for properly deleting a 'red' engine ... - Rawze - 04-17-2026
Assuming that you live in a country that has high sulfur diesel, where it is necessary to remove these system...
These are the Programming changes necessary for properly delete (de-mandate) a cummins engine so that it does not suffer any premature engine or component failures ...
== (Required): Engine operating mode control re-mapping.
*** (reason): Without heavy editing of the engine mode control logic, the engine will enter and get stuck permanently in one or more of its "rapid after-treatment warm-up mode(s)" once the exhaust system(s) are disabled, defeated, or otherwise hollowed out. The consequence is perpetual accelerated wear and friction by a large degree, significantly shortening engine and turbocharger lifespan.
The engine has several "modes" it runs in just like the different channels on an old TV set. Modes like <DPF warm-up>, <several EGR+ modes> where EGR gas is used heavily, <several different DPF and SCR cleaning modes>, and <Parked regen> mode, etc. The logic to select these modes as VERY simple and dumb. it is NOT gong to skip the DPF warm-up mode if you remove the DPF... perpetually getting stick there if the mode control logic itself is not changed to stop it. This will happen even if someone turns off all of the after-treatment management itself in the programming. The mode control logic is simply too dumb to know any better, and is a completely separate system from any of the other engine systems.
== (Required): Properly switching OFF of the input, output, and management logic/circuits for the after-treatment and EGR systems without hiding and blocking multiple faults.
*** (reason): If this is incomplete, and faults are hidden instead, then it becomes difficult to troubleshoot the engine and its remaining systems. Mechanics will often chase 'ghost' issues instead of seeing faults that would otherwise prevent premature failures. Disabling turbo, exhaust/intake pressure sensors and alarms makes the engine and turbo susceptible to repeating failures without warnings.
== (Required): ALL of the auxiliary emissions systems that become activated once the main emissions systems are disabled need to be switched OFF.
*** (reason): These systems will try to clamp and control engine output directly, even to the extent of shortening engine live, and causing harm in the process.
== (Required): Removing all EGR and aux. emissions system compensations from the injection timing, fuel-air-mix, and other combustion-related processing.
*** (reason): The ECM will NOT compensate for the missing EGR gas, nor for an altered intake/exhaust system. ALL of the combustion process settings from factory are moderately to extremely harmful once the emissions and EGR systems have been removed. Engine life will be cut in half or less if this is not done.
There is no such thing as "leaving everything as factory as possible" because it leads directly towards a significantly shortened engine and/or turbocharger lifespan. Many people tend to use excuses, blaming the components and the engine itself for the issues it suffers instead of the bad programming practices (or lack of necessary changes thereof) that were done.
======================
The ECM (engine control module) has ZERO intelligence, unlike what many people believe. It will NOT compensate for missing EGR gas. It will NOT compensate for altered exhaust flow, or anything else. Once a system on sensor or system input reads zero (or simply does not change values) all the time, it is considered 'stuck in range' and the ecm uses a default expected value, and NOT the value for an input that is now reading zero or missing. It default to assume that all of the EGR gas, etc. is still there.. and every other system that was disabled of switched off otherwise.
I.E.> If ANY of the above things are NOT done, or done incorrectly, skipped, or worsened by bad or incomplete programming, then the engine and/or turbo will suffer a shortened life, leading to repeated premature failures. These failures can happen right away on an engine driven hard, or sometimes take a couple years to progress if driven not so hard.. but they will happen.
These are the main points that I look for when reviewing someones 'custom tune' or de-mandate file...
== More than 80% of files that I review each year, the largest issue is that engine mode control was not done at all, or was done incorrectly. This alone leads to repeated engine failures such as pre-mature dropped liners and blown head gasket. This also shortens turbocharger lifespan by a LOT due to it over-spooling all the time, the engine trying with all its might to create extra exhaust heat all the time to warm up a DPF can that is no longer there. - The reason is likely that most of the people doing engine 'tuning' have no idea that multiple engine operating modes, nor its logic even exists, nonetheless how to properly edit it.
== The second most common harmful issue is that most de-mandate files that I review have harmful injection timing left in them left over from the factory setting s that have not been altered at all, or more commonly, have been made exponentially worse by someone adjusting it incorrectly, usually going the wrong direction by several degrees. This is the second most harmful thing that is done inside of bad de-mandate programming.
It seems there is a serious lack of understanding of what injection timing actually is, and how to properly adjust it in a modern diesel engine. Incorrect injection timing by only a couple-three degrees in a modern ISX will lead to fuel impingement issues on the more mild side of things, to accelerated exhaust valve seat wear with a couple more degrees, to outright dropped liners and repeated head gasket failures when out by a few more degrees,.. to cracked cylinder head, burned injector tips, and other severe engine damage cause by excessive internal friction.
Right along with this, is improper fuel-air-mix and other combustion related settings. They are just as important to correct when the engine is de-mandated.
== The third most common problem is de-mandate files where someone has shut off alarms like turbo over-spooling. It is common to see a disabled the exhaust pressure sensor and/or alarms, and several other alarms or inputs that would let someone know that the engine was not actually running quite right. Combine this with other bad things mentioned, and things like repeating turbo failures happen,.. and most of the time, the 'tuning guy' instead of knowing what is wrong.. everyone blamed the failing turbo and makes claims similar to "it can't handle the delete" and other common excuses out of sheer ignorance.
RE: Programming changes necessary for properly deleting a 'red' engine ... - Nhollis - 04-20-2026
Interesting read. When you talk about injection timing. Which way would you go. Retard or advance?
RE: Programming changes necessary for properly deleting a 'red' engine ... - marek4792 - 04-20-2026
Find the Mamas Milk Money manual post using the search function and read it thoroughly. It'll tell you what you should do depending on what you're trying to do.
RE: Programming changes necessary for properly deleting a 'red' engine ... - Rawze - 04-20-2026
(04-20-2026 )Nhollis Wrote: Interesting read. When you talk about injection timing. Which way would you go. Retard or advance?
that is a discussion for my mumble server.
info: https://rawze.com/forums/showthread.php?tid=10426&pid=85550#pid85550