Abstract: An apparatus and a method for testing the integrity of fuel tanks for leaks are disclosed. A microprocessor controls the pressurization of the fuel tank and then selectively allows the gas within the fuel tank to decay through any leaks within the tank or through the combination of the leaks within the tank and a reference orifice. By computing and comparing the time required for the tank pressure to decay between predetermined pressure levels due to any tank leaks with a standard decay time, a determination can be made whether the leakage rate through the tank is acceptable. Greater resolution, if necessary, is provided by computing the ratio of the time required for the tank pressure to decay between predetermined pressure levels through the combination of any tank leaks and a reference orifice versus only through the tank leaks and compares same against a standard ratio to determine whether the tank leakage rate is acceptable.

Abstract: An electronic fuel injector tester which permits fuel injectors to be tested when a car is at idle is disclosed. The fuel injector tester is in the form of a probe and detects the impact or vibration which occurs when the pintle within a fuel injector opens by using a piezoelectric transducer provided in the pistol-type handle of the tester. A light emitting diode provided in the pistol-type handle flashes each time the pintle within the fuel injector opens and the piezoelectric transducer emits an audible sound each time the pintle within the fuel injector opens. The fuel injector tester remains in the “sleep” mode when not in use and is activated by tapping the tester on a hard surface. When testing has been completed, the fuel injector tester automatically goes back into the “sleep” mode.

Abstract: An electronic fuel injector tester which permits fuel injectors to be tested when a car is at idle is disclosed. The fuel injector tester is in the form of a probe and detects the impact or vibration which occurs when the pintle within a fuel injector opens by using a piezoelectric transducer provided in the pistol-type handle of the tester. A light emitting diode provided in the pistol-type handle flashes each time the pintle within the fuel injector opens and the piezoelectric transducer emits an audible sound each time the pintle within the fuel injector opens. The fuel injector tester remains in the “sleep” mode when not in use and is activated by tapping the tester on a hard surface. When testing has been completed, the fuel injector tester automatically goes back into the “sleep” mode.

Abstract: An apparatus and a method for testing the integrity of fuel tanks for leaks are disclosed. A microprocessor controls the pressurization of the fuel tank and then selectively allows the gas within the fuel tank to decay through any leaks within the tank or through the combination of the leaks within the tank and a reference orifice. By computing and comparing the time required for the tank pressure to decay between predetermined pressure levels due to any tank leaks with a standard decay time, a determination can be made whether the leakage rate through the tank is acceptable. Greater resolution, if necessary, is provided by computing the ratio of the time required for the tank pressure to decay between predetermined pressure levels through the combination of any tank leaks and a reference orifice versus only through the tank leaks and compares same against a standard ratio to determine whether the tank leakage rate is acceptable.

Abstract: An apparatus and a method for testing the integrity of fuel or gas caps for leaks is disclosed. A microprocessor controls the pressurization of an air reservoir which selectively allows air to pass to either the combination of the fuel cap under test and a reference orifice or to only the reference orifice and computes the ratio of the time required for the pressure within the air reservoir to drop between predetermined pressure levels for the combination of the fuel cap under test and the reference orifice versus only the reference orifice and compares same against a standard ratio to determine whether the leakage rate through the fuel cap meets an acceptable limit.

Abstract: A device for testing an automobile's fuel delivery system, including each of the components thereof, is disclosed. The device performs a number of tests to check the ability of the fuel delivery system to maintain pressure, to determine the static and dynamic flow rates through each of the fuel injectors in the fuel system and to determine the ability of the fuel system to deliver sufficient fuel during wide-open throttle operation.