Patent Document ID: 20100274467
Application ID: 12766030
Patent Flag: 0

Claim One:
1. A fuel-pressure controller for a direct injection engine having a low-pressure pump and a high-pressure pump, the low-pressure pump pumping up a fuel in a fuel tank and supplying the fuel to the high-pressure pump, the high-pressure pump pressurizing the fuel and discharging a high-pressure fuel toward a fuel injector, the fuel-pressure controller comprising: a low pressure fuel control means for controlling the low-pressure pump in such a manner that a fuel pressure in a low pressure fuel passage agrees with a target low fuel pressure; a high fuel pressure sensor detecting a fuel pressure in a high pressure fuel pressure passage through which the fuel is supplied from the high-pressure pump to the fuel injector; a learning means for executing the low pressure fuel control in a case that a specified learning execution condition is satisfied while a fuel discharge operation of the high-fuel pump is stopped, the learning means for learning a control error in the low pressure fuel control based on a difference between a high fuel pressure detected by the high-fuel-pressure sensor and the target low fuel pressure; and a correction means for correcting a control amount of the low pressure fuel control based on the control error learned by the learning means.