Engine Controller EGR Hose Disconnection Detection
Solution Overview
Problem
Existing engine systems face challenges in timely detection and addressing of EGR system degradation due to a disconnected upstream hose of the EGR differential pressure sensor, leading to increased emissions, reduced fuel economy, and engine knock, as current monitoring methods are complex and may not identify disconnections promptly.
Innovation Solution
The engine controller monitors engine parameters such as integrated knock intensity, adaptive spark retard, and fuel control correction to infer EGR system degradation, sets the EGR rate to zero, and performs an active diagnostic test to confirm the disconnection, adjusting spark timing and fueling accordingly to mitigate knock and emissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If redundant sensors and methods for determining EGR flow are used, then EGR system reliability is improved, but device complexity increases
Solution Approach 1:
The EGR differential pressure sensor performs self-diagnosis by monitoring its own upstream hose for disconnections using existing engine parameters (knock intensity, spark retard, fuel control correction) without requiring additional redundant sensors. The sensor leverages the engine's natural operational data to detect its own faults, achieving self-monitoring functionality.
2Reliability
If periodic monitoring of EGR system components is performed, then EGR system reliability is improved, but loss of time occurs due to delayed detection
Solution Approach 1:
The system continuously monitors engine parameters (knock intensity, adaptive spark retard, fuel control correction) that provide real-time feedback about EGR hose disconnection status. This continuous feedback loop enables immediate detection of disconnections as they occur, rather than waiting for periodic monitoring intervals, thus reducing detection time while maintaining reliability.
3Object-generated harmful factors
If the upstream hose disconnection is not detected timely, then emissions increase and fuel economy deteriorates, but detection complexity increases
Solution Approach 1:
The existing engine control system serves dual purposes: it continues to control engine operation while simultaneously detecting EGR hose disconnections by analyzing its normal operational parameters (knock sensor output, spark timing adjustments, fuel control corrections). This self-service approach enables emission monitoring and fault detection without adding separate detection systems, reducing overall complexity while addressing emissions concerns.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach allows for reliable identification and timely addressing of EGR hose disconnections, reducing engine knock, improving fuel economy, and extending engine component life while enhancing exhaust emissions quality.
Implementation Method 1
When EGR flows through the EGR passage, a pressure drop occurs across the metered orifice, which is measured by the differential pressure sensor and used to determine the EGR flow rate.
Implementation Method 2
monitoring engine parameters such as integrated knock intensity
Data Source
AI summary
Methods and systems are provided for adjusting spark timing and fueling in an engine in response to an indication of exhaust gas recirculation (EGR) system degradation due to a disconnected upstream hose of an EGR differential pressure sensor. In one example, a method may include, responsive to an integrated knock intensity being greater than a threshold intensity and a fuel control correction being greater than a threshold enrichment, setting an EGR rate to zero and triggering an EGR differential pressure sensor upstream hose diagnostic routine to be performed. Further, spark timing and fueling may be set for zero EGR.