Apparatus and method for evaluating fuel injectors

1. A fuel injector for an internal combustion engine comprising:

a nozzle disposed at a distal end of the fuel injector and having at least one discharge port;

a needle slideably mounted inside the fuel injector and the nozzle;

a fluid cavity disposed in the nozzle;

a pressure sensor arranged to measure pressure in the fluid cavity; and

an orifice disposed in the needle and disposed along an outer boundary of the fluid cavity, wherein the pressure sensor is disposed in the orifice.

2. The apparatus of claim 1 , wherein the pressure sensor is a piezoelectric quartz transducer.

3. A method comprising the steps of:

charging a fuel injector for an internal combustion engine with fluid;

discharging the fluid from at least one discharge port in a nozzle disposed at a distal end of the fuel injector;

communicating fluid to a pressure sensor through a first orifice disposed in the nozzle;

communicating fluid to the pressure sensor through a second orifice in a needle inside the nozzle of the fuel injector; and

measuring fluid pressure near the at least one discharge port with the pressure sensor.

4. The method of claim 3 , further comprising the step of containing the fluid discharged from the nozzle in a chamber.

5. The method of claim 4 , further comprising the step of controlling the operating pressure of the chamber.

6. The method of claim 3 , further comprising the step of measuring the fluid discharge rate after each discharge of fluid from the nozzle of the fuel injector.

7. The method of claim 3 , wherein the pressure sensor is a piezoelectric quartz transducer.