fuel pump operation lancer evo 6 plugins

[maxime]

bonjour je souhaiterais plus d'informations sur le contrôle de la pompe à essence

voici le schéma :

 

L'entreprise qui répare ma voiture me dit qu'elle a un problème avec la commande de la pompe à carburant. Apparemment il ne fonctionnera pas tout le temps avec la même tension. Je ne vois pas comment la pompe peut tourner de plus en plus vite quand le contrôle se fait par deux relais

Merci pour votre aide afin que je comprenne.

[maxime]

[Adamw]

The Evo 6 has a 2 speed fuel pump control.  The default fuel pump settings are shown in the screenshot below.   

In your diagram the relay on the left is the main power supply relay, this turns the pump on or off, it is controlled by Inj 5 output.  The relay No2 on the right side of your diagram switches the pump between low speed and high speed mode.  This relay is a "normally closed" type, when it is not energised the contacts are closed so the current from the first relay flows directly to the fuel pump (full battery voltage).  For low speed mode the ecu energises Relay No2 so its contacts open, the current then has to travel through the resistor to reach the fuel pump - the voltage that reaches the pump will be about 9V instead of about 14V. 

Typically low speed mode is just used to lower pump noise at idle.  With the settings below the fuel pump is in lowspeed mode when RPM is below 2000 and injector duty cycle is below 5%.  When RPM OR duty cycle is exceeded then the pump switches to high speed mode.  

 

[maxime]

perfect thanks for the explanations