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The system of multi-point fuel injection (MPFI) and information gauges - the description
The system of multi-point fuel injection (MPFI) supplies to the engine a mixture of the desired quality under all operating conditions of the vehicle. The injectors provide a fuel injection system in each of the inlet ports. The brain of the system is the injection control module PCM. RSM is located in the front corner of the engine compartment. PCM receives and processes the amplitude (voltage) signals from a plurality of different sensors, switches and relays. All incoming signals are converted into digital data read by the control module is carried out on the basis of their analysis of the constant fine-tuning of the most important parameters of the engine, as the ignition timing, the duration of the inclusion of the current of the ignition coil, the pulse enable injector and engine idle speed in order to minimize air pollution combustion products, and get the most from the engine. In addition, the PCM controls the operation of the cooling fan, charging current generator and such components of emission control as electromagnets and EGR purge of a coal adsorber system EVAP. PCM is also able to change their program in accordance with the terms and conditions of work. Components of systems of decrease in toxicity of the fulfilled gases and engine management models 4.0 liters (5.2 liter models is similar to the scheme)  | | |
PCM continuously monitors the set of their own input and output circuits. If a fault occurs in the system MPFI information about it is recorded in the memory module. Perform troubleshooting system components MPFI without special costly factory manufacturing tool and reader fault codes DRB II (?�� P-4805), or its equivalent is not possible, but in many cases you can try to locate the source of the suspected failure by limiting the search range at least until a specific circuit. This work always begins with the reading of fault codes, then made a visual inspection of the system components in order to verify the condition and reliability of fastening of wiring and electrical connectors. The most common cause of failure is just loose or disconnected electrical terminal connections or the vacuum lines. For instructions on displaying diagnostic information from the PCM memory of a control lamp "Check up the engine", see Section Description of the principle of the system of self-diagnostics and procedure of reading of codes of malfunctions. Information gauges Among the variety of sources, transmitting data to the PCM includes: - Relay clutch air conditioner
- Relay automatic fuel shut-off (ASD)
- The gauge-switch of stoplights
- Camshaft position sensor
- Air temperature sensor
- Coolant temperature sensor
- The crankshaft position sensor
- The gauge of absolute pressure in the pipeline (MAP)
- Oxygen sensor
- Throttle Position Sensor (TPS)
- The gauge-switch start authorization (transmission position)
- Vehicle speed sensor (VSS)
Relay clutch air conditioner (A / B) The relay clutch K / PCM controls. Management is carried out by on-off switch circuit ground. When the PCM receives a request from the control panel K / V (Climate Control System), he gives the command to switch the motor system of stabilization of turns of idling (IAC) with a view to appropriate adjustment turns. Relay clutch control K / V is located in the center of the distribution of power next to the battery.  |
Location center power distribution. |
Relay automatic fuel shut-off (ASD) If there is no signal of ignition (distributor) or from sensors or the position of a crankshaft when the ignition key to position RUN (Movement), ASD relay shuts off power to the electric fuel pump, fuel injectors, ignition coils and heated oxygen sensor. The trip relay is located in the center of the distribution of power next to the battery. Camshaft position sensor Camshaft position sensor includes a semiconductor working on the Hall effect, and outputs a signal that is used to synchronize the operation of power systems and ignition. The synchronizing signal generated by the rotation of the ring a semiconductor sensor with a screen disposed in the distributor.  | Camshaft position sensor Engine 4.0 l. |
Air temperature sensor Air temperature sensor mounted in the intake manifold determines the temperature of the incoming air, and transmits relevant information to the PCM. Information used by the module for adjusting the air-fuel mixture.  | Location temperature sensor on the engine of 4.0 l. |
 | Location temperature sensor on the engine of 5.2 liters. |
Coolant temperature sensor Coolant temperature sensor, is screwed into the body of the thermostat, the coolant temperature monitors, sending appropriate signals to the PCM. These data, together with information received from the temperature sensor module are used to adjust the quality of the combustible mixture and the idling speed of the engine is warming up. The sensor also turns on the blower radiator.  | Location of engine coolant temperature sensor is 4.0 liters. |
 | Location of engine coolant temperature sensor is 5.2 liters. |
The crankshaft position sensor The crankshaft position sensor is mounted on the dome of the transmission. The sensor transmits a PCM information about the current position of the crankshaft. The initial data used sensor slots on the drive or disk drive rotating flywheel.  | Location crankshaft position sensor engine 4.0 liters, equipped with AT. |
 | Location crankshaft position sensor engine 4.0 liters, equipped with Manual transmission. |
The gauge of absolute pressure in the pipeline (MAP) The MAP sensor is located on the bulkhead or wall of the engine compartment. The sensor determines the depth of the vacuum in the intake manifold through a vacuum line connected to the throttle body. Take readings on the sensor transmits PCM, together with data on barometric pressure in the form of changing the amplitude of the voltage. In conjunction with information obtained from other sensors, these data allow the control module to determine the desired composition of the combustible mixture.  | Location MAP sensor on the engine 4.0 liters. |
 | Location MAP sensor on the engine 5.2 liters. |
Various sensors, switches Sensor switches (such as switch start authorization, air conditioning, speed control and brake lights) PCM supply information to enable it to make the adjustment operation of the engine depending on the status of various equipment (incl. / Off.). Indication of sensor data-switching (high / low signal level) is difficult to determine without a diagnostic meter DRB II. Oxygen sensor The oxygen sensor is located in a reception pipe exhaust system (right on the engines V8), gives the amplitude (voltage) signal depending on the presence of exhaust gas oxygen. To speed up the output of the sensor to the operating mode with the engine warming the sensor is equipped with a built-in electric heater. If the exhaust gas contains a significant percentage of oxygen (lean mixture), the sensor signal has a smaller amplitude; at low oxygen content (rich mixture), the amplitude of the voltage emitted by the sensor increases. Tracking the percentage of oxygen in the exhaust gases and converting it to an electrical signal, the sensor operates as a sensor switch depletion-enrichment combustible mixture. The signal from the sensor is supplied to a PCM that based on its analysis of increases or decreases the pulse width (duration) including fuel injectors.  | Location of oxygen sensor. |
Throttle Position Sensor (TPS) Located in the throttle TPS determines the angle of deflection of the throttle. Formed by a sensor voltage is increased or decreased depending on the width of the opening flap. By doing this on a PCM signal is coupled with the data obtained from other sensors, the module allows the processor to carry out quality adjustment mixture depending on engine operating conditions such as acceleration / deseleratsiya work at idle or full throttle.  | Location TPS (5.2 liter engine). |
Proximity sensor (speed) of a vehicle (VSS) VSS, located on an extension of the transmission housing or transfer case (depending on the equipment of a vehicle) is used to determine the vehicle speed. The sensor generates eight pulses per revolution of the drive shaft and transmits them to the PCM. These signals are compared module signal the closed throttle position of TPS allow to distinguish between the state of closing the valve when resetting the engine speed and the last at idle (at stand still car) By dropping the engine speed PCM monitors the operation of the motor IAC, achieving the desired signal IDA; when the engine is idling, the PCM controls the motor IAC, maintaining the desired engine speed.  | Location VSS. |
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