Cummins has published a helpful guide to engine sensors. Apparently modern engines can monitor emissions, detect NOx, analyse exhaust gases, feed real-time information into control units and build a picture of how an engine behaves in real-world conditions. This is fantastic news. If only there had been some way of knowing what Cummins engines were fucking emitting.
There are corporate articles that require forensic analysis.
There are corporate articles that require several documents open beside them, a strong coffee and half an afternoon following footnotes through the machinery.
Then there is Cummins publishing The Role Of Sensors In Engines.
On 11 September 2026.
After the defeat-device scandal.
Beautiful.
Cummins Discovers Sensors
Cummins begins by explaining that sophisticated sensors and control units function rather like the nerves and brain of an engine. Sensors gather information. Control units receive it. Software compares the information with programmed operating parameters, then actuators can make adjustments.
Very clever.
You could almost imagine a modern diesel engine knowing what it was doing.
Cummins even gives us a practical example involving exhaust-manifold output. Measure what is happening, determine whether fuel timing is working correctly and adjust the system if necessary.
So far, so educational.
Then Cummins wanders directly onto the rake.
They Can Monitor Emissions
Commercial vehicles, Cummins explains, contain sensors monitoring pressure, temperature, airflow, fluid quality, engine speed and emissions.
Not just vaguely sniffing around the exhaust pipe either.
Chemical sensors can detect NOx, oxygen, ammonia and particulate matter. Diesel engines specifically require NOx sensors. Aftertreatment brings another collection of sensors and onboard diagnostics into the equation.
The information is available in real time.
Cummins says that information helps electronic control systems manage fuel efficiency, reliability, performance and “emissions compliance”.
Emissions compliance.
From Cummins.
Fucking magnificent.
Somewhere in Columbus, Indiana, somebody apparently read those two words together, nodded thoughtfully and pressed publish.
The Engine Has Eyes
The real beauty comes later.
Cummins explains that sensor technology, analytics and software increasingly allow powertrains to operate intelligently. Sensor inputs can tell the control system about temperature, pressure, vibration, fluids and emissions.
All of that information, Cummins says, provides a clearer picture of engine performance in real-world conditions.
Real-world conditions.
There it is.
Three words walking unattended through a Cummins emissions article without an adult anywhere in sight.
Because according to the US Environmental Protection Agency, the problem with approximately 630,000 model-year 2013-2019 Ram 2500 and 3500 diesel vehicles was rather specifically what happened outside the fucking test.
EPA found software defeat devices in the Cummins-certified engines. During emissions compliance testing, the software activated full emissions controls. During other normal operating conditions, those software features reduced or deactivated emissions controls.
The sensors were not the stupid part.
Apparently Software Can Make Decisions Too
This new Cummins article is wonderfully enthusiastic about the relationship between sensing and software.
The sensor gathers information. The control unit interprets it. Programmed parameters determine what should happen next. Actuators respond. Modern systems increasingly make real-time decisions.
Yes.
We know.
That is approximately where Cummins might have considered quietly closing the laptop and publishing something about fucking oil filters instead.
EPA’s settlement record says Cummins configured emissions software features as defeat devices that reduced or deactivated engine emissions controls. About 630,000 vehicles had illegal defeat-device software, while roughly another 330,000 contained previously undisclosed auxiliary emission control devices.
Nearly one million vehicles sat inside the wider settlement.
Then, two and a half years later, Cummins newsroom staff arrived to explain the exciting relationship between sensors, software, emissions and programmed control strategies.
Thanks, lads.
We had picked up some of the basics.
NOx Sensors: What An Extraordinary Innovation
The Cummins explainer is particularly pleased with chemical sensors.
These clever little bastards can detect exhaust NOx.
That is useful because NOx emissions are quite important when you are manufacturing diesel engines subject to emissions limits.
EPA says the defeat devices resulted in affected vehicles producing NOx emissions at levels substantially higher than applicable standards during normal driving conditions. The resulting settlement carried a $1.675 billion civil penalty, alongside more than $325 million in estimated remediation costs.
Imagine having a sensor capable of detecting NOx while simultaneously operating inside a corporate history featuring the largest civil penalty ever assessed under the Clean Air Act.
Technology really is incredible.
Onboard Diagnostics Get A Gold Star
Cummins also wants us to appreciate the standards involved in onboard diagnostics.
Sensors must remain durable. They need to function over the life of the vehicle. Engineers have to demonstrate that components can keep doing their jobs after years of wear.
Cummins describes that as a high bar.
It is certainly one bar.
Another might be ensuring the fucking emissions controls remain fully effective when the vehicle leaves the laboratory.
But perhaps that belongs in the advanced course.
A Clearer Picture Of Real-World Conditions
This is what makes the article so funny.
Not the existence of sensors. Cummins obviously knows a great deal about sensors. It is a huge engineering company with decades of diesel expertise, thousands of engineers and enormously sophisticated electronic control systems.
That is precisely the point.
This is not some bloke discovering a warning light in his Transit.
Cummins is explaining, in loving technical detail, how engines gather data about themselves. Pressure. Temperature. Airflow. Exhaust composition. NOx. Particulate matter. Vehicle speed. Engine speed. Aftertreatment. Diagnostics. Software. Real-time control.
The engine is practically filling in its own witness statement.
Cummins then tells us these technologies help engineers understand what happens in real-world conditions.
Yes.
Again.
We fucking know.
The Software-Defined Era
Cummins finishes by looking towards what it calls the software-defined era of heavy-duty power.
More sensing. Better analytics. Smarter controls. Improved diagnostics. Increasingly connected engines making ever more precise decisions.
There is probably an excellent future in it.
Provided, obviously, nobody programs the clever fucking software to recognise when it is taking an emissions test.
The sensors know what the engine is emitting.
The control unit knows what the sensors are saying.
The software knows what operating conditions it is seeing.
And now Cummins has published an article explaining the whole arrangement for anybody who might somehow have missed the previous demonstration.
Outstanding corporate content.
As you were.
Lee Thompson – Founder, The Cummins Accountability Project
Sources
- Cummins – The Role Of Sensors In Engines
- US Environmental Protection Agency – 2024 Cummins Inc. Vehicle Emission Control Violations Settlement
- US Environmental Protection Agency – Cummins Violation Of Clean Air Act Vehicle Emission System Controls Requirements FAQ
- US Department Of Justice – Cummins Agrees To Pay Record $1.675 Billion Civil Penalty In Vehicle Test Cheating Settlement