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I seem to be getting all sorts of information on our fuel system. Of course doing a search is simple but due to all the cris-crossing information, it's hard to find out whats right. Ok, so here it is, the BIG question, that is:
Our fuel is regulated by the amount of O2 detected in the exhaust. Thus our ECU reacts to either increasing or cuting fuel depending on the situation.
Now, what I want to know is, how does it do that? Increasing the duty cycle of the injectors right? What about the pump? I hear the Ford Focus returnless fuel system ALSO regulates the current in their fuel pump to increase/decrese fuel pressre along with icreasing/ decreasing injector cycle. Because the amount of fuel being sent depends on two things. Pressure and duty cycle. We have no return line thus no pressure regulator. Does that mean our pump is current reglated or just injector cycle regulated?