Patent · US Expired

Fuel pump diagnostics for internal combustion engine

US4094191A · kind A · utility

12Cited by
1References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1977
Grant dateJun 13, 1978
Priority date
Expiry dateMar 25, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01M13/003
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A single pressure transducer tapped into the fuel system of an engine, at a point to be responsive to the pressure of the fuel operating against the pressure regulating bypass valve of the fuel system, is used to measure fuel pressure at low idle speed and at high idle speed of the engine; the two pressures when compared against normal pressure can determine bypass valve condition since lower than normal pressure at low idle speed in combination with normal pressure at high idle speed is an indication of a bypass valve which is stuck in the open position, and higher than normal pressure at high idle speed is indication of a bypass valve which is stuck in the closed position. The test can also discern other faults since a lower than normal pressure at high idle speed in combination with a lower than normal pressure at low idle speed is indicative of a bad pump. And, a normal pressure at low idle speed and a lower than normal pressure at high idle speed together are indicative of a filter or other restriction in the line. An exemplary process for making the fuel pressure measurements at two different speeds and a simple illustration of diagnostic analysis of the results thereof are d…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.