Apparatus and a method for diagnosing an exhaust gas purification system

Patent · Tue Sep 13 00:00:00 EDT 1988

OSTI ID:6665605

Shibata, N; Uchitani, N

This patent describes a method for diagnosing at least three sensors of an exhaust gas purification system, which includes a predetermined relationship between outputs of the three sensors comprising: detecting an output of a first sensor of the three sensors; detecting an output of a second sensor of the three sensors; detecting an output of a third sensor of the three sensors; detecting an engine revolution number; and determining whether the engine revolution number is within a first revolution range when the output of the second sensor is contrary to an output predicted in accordance with the outputs of the first and third sensors on the basis on the predetermined relationship, whereby the method does not diagnose any of three sensors as out of order when the engine revolution number is within the first revolution range.

• Assignee: Toyota Jidosha Kabushiki Kaisha, Aichi
• Patent Number(s): US 4770146
• OSTI ID: 6665605
• Resource Relation: Patent File Date: Filed date 21 Sep 1987
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
54 ENVIRONMENTAL SCIENCES
EXHAUST GASES
PURIFICATION
INTERNAL COMBUSTION ENGINES
POLLUTION CONTROL EQUIPMENT
METERING
AIR POLLUTION CONTROL
DETECTION
FUEL SYSTEMS
OPERATION
CONTROL
ENGINES
EQUIPMENT
FLUIDS
GASEOUS WASTES
GASES
HEAT ENGINES
POLLUTION CONTROL
WASTES
330100* - Internal Combustion Engines
330700 - Advanced Propulsion Systems- Emission Control
500200 - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)