Truck & Diesel Engine Computers
Diesel Engines vs. Gasoline EnginesI'll bet that you've heard of diesel engine (and have probably seen the diesel pumps at the gas station), but Iw would also bet that you don't really know what a diesel engine is. At the core of their function, both gas and diesel engines are pretty similar. They both convert chemical energy into mechanical and kinetic energy, and do so through the process of internal combustion. For this reason, they are both called internal combustion engines.
The difference is how that combustion is achieved. In gasoline engines, the air and fuel mixture is compressed until, at a critical point in the timing of the engine cycle, a spark plug ignites the air-gas mixture.
In diesel engines, on the other hand, there are no sparks or spark plugs involved. Instead, the diesel fuel and air are compressed together to the point until it combusts. Basically, the extreme compression generates enough heat that the mixture spontaneously combusts in a process known as "combustion ignition."
What Does Diesel ECM/PCM Do?In diesel engines, the diesel computer controls the injection of the fuel and air into the cylinder, as well as the compression of the mixture. This is especially important when starting a diesel engine in cold weather, as the compression process required for combustion may not raise the air to a high enough temperature to ignite the fuel.
The diesel computer, or diesel control module (DCM) can sense the ambient air temperature and adjusts the timing of the engine in cold weather so the injector sprays the fuel at a later time. The air in the cylinder is compressed more, creating more heat, which aids in starting.
Additionally, the computer in your diesel engine controls or regulates the following functions:
• Ignition system
• Fuel injection
• Emission system
• Mechanical positioning of the rotating assembly
• Exhaust system
• And any other functions related to the operation of the engine and transmission
The same as the car computer in a gasoline engine vehicle, a diesel computer is able to control and regulate all these functions by utilizing a vast system of sensors and switches throughout the engine. These sensors provide a constant stream of information and data that the computer uses to make adjustments to diesel engine components in order to ensure a smooth operation in the face of changing driving and engine conditions.
Diesel engine computers will also run and store an error code related to the system or component it thinks is causing the problem. This then makes the job of a mechanic or technician that much easier, because they can better pinpoint which part of the engine is having trouble.