Fuel pressure sensor

    The pressure sensor is designed to provide output data to a computer for display on the terminal pressure of the injection. The integrity of the sensor is essential for the proper operation of the engine. Sensors are marked 7700113205.

     The sensor is one of the least unreliable and fuel system components without the need for it is better not to move. The sensor is powered by a 5V voltage depending on the pressure and the output voltage varies from 0.5 to 3.2 V. Voltage is 0.5 V in the absence of pressure, or a very low pressure (5 bar with pre-pump). With the increase in pressure increases and the voltage about 3.2 V, the critical pressure of 125bar engine. In normal operation conditions, it should not fall below 2.2 V and exceed the 3V depending on engine speed and load which corresponds to a pressure of 60-90bar. After warming up at idle is about 2.6 V. The method is very approximate, but allows for an initial diagnosis without a computer.

      In the event of damage to the pressure sensor trips the engine is turned off. Faulty sensor is not suitable for repair and should be replaced with a new one or a good one coming from the disassembly.   

Disassembly of pressure sensor

Very important!
     The pressure sensor can be removed only on a cold engine. To be safe, also have a fire extinguisher nearby. An attempt to remove the hot engine can cause a fire. The fuel is under high pressure and temperature is about 100 ° C. Unsealing of such a system leads to the immediate point of gasoline and throw it out, which can cause ignition and explosion of fumes or burns.

     Spanner [27], unscrew the sensor. In the absence of such a key, remove the regulator and remove the sensor wrench. Despite the large diameter screw valve key is quite low torque, it has a fine thread and is screwed into the aluminum rail. No need to loosen the sensor should not be as easy to break the thread of the rail.
 
     Absolutely not attempt to loosen the sensor by holding the plastic seat, very easy to break or turn the housing, then the break is fine jointing tape.

     The tightness of the system is essential for the proper operation and safety. Therefore, all the operations you perform at your own risk.

Construction of the sensor

Look inside the pressure sensor, piezoelectric sensor is located under the board electronics











The sensor is protected by MLX12106E and thus is resistant to short pins, connecting higher than 5V voltage (up to 14V) and polarity. With this construction is almost fail-safe system. Operating range from-40C to 150C











Sensor connection

Wiring diagram of the pressure sensor to the computer Sirius 35 (Laguna II). Mark [Y] is the middle slot of your computer.
In the case of incorrect reference pressure (over 170 bar or below zero) it is necessary to check the correct connection of the sensor to the computer.



















Pressure sensor F5R Team

Pressure sensor Team F5R for the  IDE engine. This is an inductive sensor so is more durable than the original piezoelectric sensor.