boomtheroom Posted June 22, 2020 Author Report Share Posted June 22, 2020 if i run 2 control modules (2 fule pumps) i can use pin 6 to activate both relays from the battery to the controllers then use aux1 and aux2 to each controller? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 22, 2020 Report Share Posted June 22, 2020 Sounds a bit more complicated than it needs to be, but yes it should work. Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 17, 2021 Author Report Share Posted June 17, 2021 REVISIT AS IM NOW ACTUALL Y GETTING CLOSER TO MY BUILD would it be easier to bypass the factory fuel controller all together? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 17, 2021 Report Share Posted June 17, 2021 What are you trying to acheive? The stock fuel pump controller is mostly there to reduce noise and possibly a little current draw when idling. For many modified cars the fuel pump noise is no longer relevant. boomtheroom 1 Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 17, 2021 Author Report Share Posted June 17, 2021 1 hour ago, Adamw said: What are you trying to acheive? The stock fuel pump controller is mostly there to reduce noise and possibly a little current draw when idling. For many modified cars the fuel pump noise is no longer relevant. yeah i was more concerned about the extra heat generated at idle in 3-+ deg in summer idling.. not worried about the noise really 30+deg so going back to the initial diagram of the factory controller.. if i bin it totally.. what is the best way to utilize the triggers available without it. i want to run one lift pump ,a main pump and a secondary pump to come on at 70/80 % full throttle linkG4x plugnplay GTR Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 17, 2021 Report Share Posted June 17, 2021 Fuel pumps heating the fuel is a myth in my experience. Well at least with any sane sized road car fuel pumps. The biggest heat source is the engine, remember you are pumping fuel through a highly conductive metal rail bolted to the cylinder head that runs at ~90°C, you also generally have a few feet of fuel pipes/hoses in the engine bay at ~80°C. The heat transfered from these sources is only influenced by the mass of the fuel in the tank and the temp difference between engine and fuel tank, the speed at which you are pumping the fuel through the rail makes no difference to how much heat is transfered to the fuel. A brushed DC motor is ~80% efficient and a vane or gerotor pump is probably somewhere similar at a guess so there is not much energy lost from the pumping process going into heating the fuel. 2 hours ago, boomtheroom said: i want to run one lift pump ,a main pump and a secondary pump to come on at 70/80 % full throttle linkG4x plugnplay GTR I dont personally like switching a large pump on/off, you always see a significant spike in pressure as the regulator responds to the increased flow. I generally use a single pump or have them all running all the time. Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 17, 2021 Author Report Share Posted June 17, 2021 1 hour ago, Adamw said: Fuel pumps heating the fuel is a myth in my experience. Well at least with any sane sized road car fuel pumps. The biggest heat source is the engine, remember you are pumping fuel through a highly conductive metal rail bolted to the cylinder head that runs at ~90°C, you also generally have a few feet of fuel pipes/hoses in the engine bay at ~80°C. The heat transfered from these sources is only influenced by the mass of the fuel in the tank and the temp difference between engine and fuel tank, the speed at which you are pumping the fuel through the rail makes no difference to how much heat is transfered to the fuel. A brushed DC motor is ~80% efficient and a vane or gerotor pump is probably somewhere similar at a guess so there is not much energy lost from the pumping process going into heating the fuel. I dont personally like switching a large pump on/off, you always see a significant spike in pressure as the regulator responds to the increased flow. I generally use a single pump or have them all running all the time. Got Ya! Might just wire in the lift and main pump bu themselves and see how much they can handle leave the 3rd inactive until things start looking lean.. That being the case shall i run the pump relays straight to the battery, then use pins 104 and 106 from the ecu to ground the relay to switch them on, and just bypass the fuel pump modulator all together? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 17, 2021 Report Share Posted June 17, 2021 Yes you will probably get better voltage at the puimps if you bypass the original controller. I would just have one relay for the lift and main pump and switch them both on together with one aux. You can save the 2nd aux for later if you need to add the 3rd pump. Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 20, 2021 Author Report Share Posted June 20, 2021 actually if i get rid of the factory module ill have aux 6,1 and 2 free? also trying to sus the factory module what role is pin 6 having? if 4 is ground? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 20, 2021 Report Share Posted June 20, 2021 8 hours ago, boomtheroom said: actually if i get rid of the factory module ill have aux 6,1 and 2 free? Yes, you will need to use one of those auxes for your new fuel pump relay. 8 hours ago, boomtheroom said: also trying to sus the factory module what role is pin 6 having? if 4 is ground? Pin 6 is a shield, pin 4 is the controlled side of the fuel pump - I assume PWMed. Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 20, 2021 Author Report Share Posted June 20, 2021 2 hours ago, Adamw said: Pin 6 is a shield, pin 4 is the controlled side of the fuel pump - I assume PWMed. Shield? what does a shield do? 2 hours ago, Adamw said: Yes, you will need to use one of those auxes for your new fuel pump relay. Pin 6 is a shield, pin 4 is the controlled side of the fuel pump - I assume PWMed. from what is see when the ignition is turned on the relay supplys power to pin 2 on the fuel pump.. if thats the case why does it also get power from pin 7 on the control unit? ir am i just confused? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 21, 2021 Report Share Posted June 21, 2021 2 hours ago, boomtheroom said: Shield? what does a shield do? https://en.wikipedia.org/wiki/Electromagnetic_shielding It looks to me like the wire from the FPCM to the pump is shielded and the shield connects to pin 6, most likely a ground. 2 hours ago, boomtheroom said: from what is see when the ignition is turned on the relay supplys power to pin 2 on the fuel pump.. if thats the case why does it also get power from pin 7 on the control unit? ir am i just confused? Pin 7 and 5 are power to the FPCM, it gets its power from the FP relay at the same time as the fuel pump. Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 21, 2021 Author Report Share Posted June 21, 2021 1 hour ago, Adamw said: https://en.wikipedia.org/wiki/Electromagnetic_shielding It looks to me like the wire from the FPCM to the pump is shielded and the shield connects to pin 6, most likely a ground. Pin 7 and 5 are power to the FPCM, it gets its power from the FP relay at the same time as the fuel pump. You've lost me :-> if fuel pump is already getting power from the relay why would it also need power from pin 7 on the fpcm? i understand the fpcm needs power form pin 5 but pin 7 feeding the pump when it already has power form the relay? appreciate the replys too ... Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 21, 2021 Report Share Posted June 21, 2021 2 hours ago, Adamw said: Pin 7 and 5 are power to the FPCM Quote Link to comment Share on other sites More sharing options...
boomtheroom Posted June 21, 2021 Author Report Share Posted June 21, 2021 2 minutes ago, Adamw said: ??? diagram says pin 7 fuel pump + ? why would the fpcm need 2 power sources? Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 21, 2021 Report Share Posted June 21, 2021 It is just a simplified diagram to show how things are connected. All you need to know is pin 5, pin 7 and the fuel pump are all connected to the same fuel pump relay pin. Most likely one of those wires FPCM wires is a voltage sense type function or similar. Quote Link to comment Share on other sites More sharing options...
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