-Manifold absolute pressure or (MAP) is the measurement of potential air. This measurement tells the PCM how much air is ready to enter the combustion chamber when the intake valve opens.
-Intake air temperature or (IAT) hot air is less dense than cold air. Volumetric efficiency, this value is stored in the PROM. It is a value measured by the engineer when the vehicle was developed that represents the amount of air that has the ability to enter the cylinder on the intake stroke at a given rpm.-
-Exhaust gas recirculation or (EGR) the PCM needs to know how much exhaust gas is being recirculated into the cylinders to effectively know the real weight of the air in the chamber. This action performed by the EGR system actually cools the cylinders to reduce NOX emissions and engine ping. Modifiers tweak the calculated values to compensate for operating conditions that always change. I recommend a good emissions repair shop for any repair EGR related.
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Unfortunately, when it comes to diesel trucks and cars, there are many things that could go wrong. Because diesel engines are larger and slightly more intricate, it may cost more to repair at an auto repair shop. They still require regular maintenance to keep them running at optimal performance. You must change the oil itself, air, oil, and fuel filters. Although cleaner diesel fuels means you are no longer required to bleed excess water out of the system, many vehicles still have water separators that need to be manually emptied. Furthermore, when you neglect the regular maintenance of a diesel engine, the fuel system could break down. If this happens, a repair can cost more money for parts and labor than a traditional gasoline engine.
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