It will be good to familiarize yourself with the sensors in Detroit engines so that you can know what is wrong with your engine.
Let’s list the sensors one by one including their functions.
1. Temperature sensor: this is the sensor responsible for monitoring the temperature of the engine. If the sensor notices that the temperature of the engine is too high, then it will pass the signal to the ECM to shut down the engine.
However, you need to note that a faulty temperature sensor can pass the wrong signal which can prevent the engine from running. So it is advisable to replace the sensor during the overhauling or major repairs.
2. Oil sensor: This is another important sensor on the DD engine. However, it is also seen in other engines such as Cummins, and Cat.
The sensor measures the oil pressure, to ensure that the oil pressure in the engine is normal. if the sensor observes low oil pressure, it immediately passes a signal to the ECM to shut down the engine. The sensor is vital to the engine, so if you notice that it is bad then you need to replace it immediately.
There was one of my clients who disconnected the oil sensor wire. I told him not to do that but he insisted that the sensor was malfunctioning. But the sensor is correct. After running the engine for about 30 minutes, the engine seized due to friction between the crankshaft and the metal.
What is the lesson; don’t ignore the warning sensor.
3. Position and speed sensor: There are several names for this sensor such as flywheel sensor, crankshaft sensor, or TDC sensor.
This is so vital to the engine to the extent that if the sensor is bad or wrongly installed the engine will not start. The sensor measures the angle and position of each piston to know when the injectors will inject. The sensor works with the ECM, when the piston is at the TDC, the sensor notifies the ECM and the ECM notifies the injector of that cylinder to atomize.
However, you should know that in some mechanical engines, this sensor is not there. It is only available in an electrical control engine.
Although there are other sensors these are the major ones.
Let’s talk about the position of the sensor on the engine.
The temperature sensor is located at the thermostat housing. While some manufacturers installed it on the cylinder head.
The oil sensor is located at the oil filter housing or on the engine block.
The flywheel sensor is located at the flywheel house to have access to the flywheel.