ENGINE GLOW PLUG DIAGNOSIS USING CRANKSHAFT SENSOR DATA

• US 20080319599A1
• Filed: 06/25/2007
• Published: 12/25/2008
• Est. Priority Date: 06/25/2007
• Status: Active Grant

• Current Assignee: International Engine Intellectual Property Company, LLC (Volkswagen AG)
• Original Assignee: International Engine Intellectual Property Company, LLC (Volkswagen AG)
• Inventors: Hsia, David M., Tran, Ly V., Ptak, Richard
• Granted Patent: US 8,150,576 B2
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: F02D 41/1497 With detection of the mechanical response of the engine
• CPC Class Codes: F02P 17/00 Testing of ignition installations, e.g. in combination with adjusting testing fuel injection apparatus F02M65/00; testing ignition installations in general F23Q23/00; Testing of ignition timing in compression-ignition engines
• CPC Class Codes: F02P 19/027 Safety devices, e.g. for diagnosing the glow plugs or the related circuits

Abstract

A motor vehicle engine (10) has glow plugs (20) for aiding combustion of fuel in combustion chambers of the engine when the engine is cold and an ignition switch (24) is operated to crank the engine. An aberration in engine speed (36) is used to indicate an under- or non-performing glow plug. Data from sources other than the engine speed source (28), such as data related to engine fueling, is also processed by a processor (30) to exclude them as the cause of the aberration.

Claims

1. A motor vehicle comprising:

an internal combustion engine that has a cold start aid for aiding combustion of fuel in combustion chambers of the engine when the engine is cold and a switch is operated to crank and fuel the engine;

a processor for initiating operation of the cold start aid in advance of cranking and fueling the engine and for using data from a crankshaft rotation sensor associated with a crankshaft of the engine to indicate under- or non-performance of the cold start aid once the engine has been cranked, fueled, and commenced running under its own power.

2. A motor vehicle as set forth in claim 1 wherein the cold start aid comprises one or more glow plugs associated with the combustion chambers.

3. A motor vehicle as set forth in claim 2 wherein the processor comprises an algorithm that during execution processes data from the crankshaft rotation sensor disclosing aberrations in engine speed and that upon processing data disclosing aberrations indicative of under- or non-performance of one or more of the glow plugs gives a signal indicating such under- or non-performance.

4. A motor vehicle as set forth in claim 3 wherein during execution of the algorithm, the processor also processes certain data related to other aspects of engine operation to exclude such other aspects as a cause of aberrations in engine speed that are otherwise indicative of under- or non-performance of the one or more glow plugs.

5. A motor vehicle as set forth in claim 3 wherein during execution of the algorithm, the processor also processes certain data related to fueling of the combustion chambers to exclude fueling of the combustion chambers as a cause of aberrations in engine speed that are otherwise indicative of under- or non-performance of the one or more glow plugs.

6. A motor vehicle as set forth in claim 1 wherein the processor comprises an algorithm that during execution processes data from the crankshaft rotation sensor disclosing aberrations in engine speed potentially indicative of under- or non-performance of the cold start aid and data for excluding potential causes of the disclosed aberrations other than the cold start aid, and that gives a signal indicating under- or non-performance of the cold start aid upon the processing excluding other potential causes as causes of the disclosed aberrations.

7. A system for indicating under- or non-performance of a cold start aid associated with combustion chambers of a compression ignition internal combustion engine when the engine is cranked and fueled after having been exposed to ambient cold that affects proper combustion of fuel injected into the combustion chambers, the system comprising:

a device for initiating operation of the cold start aid in advance of cranking and fueling the engine and a processor programmed with an algorithm for processing data from a crankshaft rotation sensor associated with a crankshaft of the engine and for indicating, once the engine has commenced running under its own power, under- or non-performance of the cold start aid when the processed crankshaft rotation data discloses an aberration in engine speed indicative of under- or non-performance of the cold start aid.

8. A system as set forth in claim 7 wherein when the processor, during execution of the algorithm, processes data from the crankshaft rotation sensor disclosing aberrations in engine speed indicative of under- or non-performance of the cold start aid also processes certain data related to other aspects of engine operation to exclude such other aspects as causes of aberrations that are otherwise indicative of under- or non-performance of the cold start aid.

9. A system as set forth in claim 7 wherein when the processor, during execution of the algorithm, processes data from the crankshaft rotation sensor disclosing aberrations in engine speed indicative of under- or non-performance of the cold start aid also processes certain data related to fueling of the combustion chambers to exclude aberration in fueling of the combustion chambers as a cause of aberrations that are otherwise indicative of under- or non-performance of the cold start aid.

10. A method for indicating under- or non-performance of an engine cold start aid once the engine with which the cold start aid is associated has been cranked, fueled, and commenced running under its own power, the method comprising:

with the engine having been soaked in cold ambient temperature that makes use of the cold start aid appropriate to aid combustion of fuel injected into the combustion chambers, operating the cold start aid and cranking and fueling the engine; and

detecting aberrations in engine speed data indicating under- or non-performance of the cold start aid once the engine has been cranked, fueled, and commenced running under its own power.

11. A method as set forth in claim 10 wherein the step of operating the cold start aid comprises electrically energizing one or more glow plugs associated with the combustion chambers.

12. A method as set forth in claim 11 wherein the step of detecting aberrations in engine speed data comprises processing data from a crankshaft rotation sensor associated with a crankshaft of the engine.

13. A method as set forth in claim 12 further including processing certain data related to other aspects of engine operation to exclude such other aspects as causes of aberrations in engine speed data that are otherwise indicative of under- or non-performance of the one or more glow plugs.

14. A method as set forth in claim 12 further including processing certain data related to fueling of the combustion chambers to exclude fueling of the combustion chambers as causes of aberrations in engine speed data that are otherwise indicative of under- or non-performance of the one or more glow plugs.