Methods and systems for detecting high friction within flow control devices

1 . A diagnostic monitoring system for detecting a high friction within a flow control device of a fuel system, the diagnostic monitoring system comprising:

a computing device; and

an engine controller communicatively coupled to the computing device and the flow control device, the engine controller and the computing device being configured to execute software to:

receive with the engine controller a service test sequence to execute a service test;

perform with the engine controller, in response to a receipt of the service test sequence, the service test to generate test data, the service test including a first test cycle with a first dither level and a second test cycle with a second dither level;

determine with the computing device whether a performance difference of the flow control device between the first test cycle and the second test cycle exceeds a predetermined threshold based on the test data; and

detect with the computing device, in response to a determination that the performance difference exceeds the predetermined threshold, a presence of high friction within the flow control device,

wherein the second dither level is different from the first dither level.

2 . The diagnostic monitoring system of claim 1 , wherein the engine controller is further configured to execute the software to cause the engine controller to:

determine, in response to a receipt of the service test sequence, whether one or more enable conditions are satisfied to execute the service test; and

transmit, in response to a determination that the one or more enable conditions are not satisfied, a notification indicating that the service test cannot be executed,

wherein the notification further includes one or more remedial actions that can be performed to satisfy the one or more enable conditions.

3 . The diagnostic monitoring system of claim 1 , wherein to perform the service test includes to control the flow control device using a high frequency pulse-width modulation (PWM) signal with a superimposed low frequency dither waveform.

4 . The diagnostic monitoring system of claim 1 , wherein to perform the service test includes to:

perform the first test cycle by applying a first amplitude of dither in a flow control device signal, and

perform the second test cycle by apply a second amplitude of dither in the flow control device signal, the second amplitude is different from the first amplitude.

5 . The diagnostic monitoring system of claim 1 , wherein the test data includes:

a first rail pressure command and a first rail pressure feedback collected during the first test cycle, and

a second rail pressure command and a second rail pressure feedback collected during the second test cycle.

6 . The diagnostic monitoring system of claim 5 , wherein to determine whether the performance difference between the first test cycle and the second test cycle exceeds the predetermined threshold includes to:

determine a first sum of absolute pressure error between the first rail pressure command and the first rail pressure feedback;

determine a second sum of absolute pressure error between the second rail pressure command and the second rail pressure feedback;

determine a difference between the first sum and the second sum;

determine whether the difference exceeds the predetermined threshold; and

detect, in response to a determination that the difference exceeds the predetermined threshold, the presence of high friction within the flow control device.

7 . The diagnostic monitoring system of claim 6 , wherein the engine controller is configured to execute the software to further cause the computing device to:

transmit, in response to a detection of the presence of high friction within the flow control device, a notification to a technician to replace the flow control device.

8 . A method for detecting a high friction within a flow control device of a fuel system, the method comprising:

communicatively coupling a computing device and an engine controller; and

operating the engine controller and the computing device to:

receive with the engine controller from the computing device a service test sequence to execute a service test;

perform with the engine controller, in response to receiving the service test sequence, the service test by controlling the flow control device to generate test data, the controlling including a first test cycle with a first dither level and a second test cycle with a second dither level;

determine with the computing device whether a performance difference of the flow control device between the first test cycle and the second test cycle exceeds a predetermined threshold based on the test data; and

detect with the computing device, in response to determining that the performance difference exceeds the predetermined threshold, a presence of high friction within the flow control device;

output form the computing device a technician-perceptible notification of the presence of high friction within the flow control device,

wherein the second dither level is different from the first dither level.

9 . The method of claim 8 , wherein the engine controller is further configured to:

determine, in response to receiving the service test sequence, whether one or more enable conditions are satisfied to execute the service test; and

transmit, in response to determining that the one or more enable conditions are not satisfied, a notification indicating that the service test cannot be executed,

wherein the notification further includes one or more remedial actions that can be performed to satisfy the one or more enable conditions.

10 . The method of claim 8 , wherein performing the service test includes controlling the flow control device using a high frequency pulse-width modulation (PWM) signal with a superimposed low frequency dither waveform.

11 . The method of claim 10 , wherein performing the service test includes:

performing the first test cycle by applying a first amplitude of dither in a flow control device signal, and

performing the second test cycle by apply a second amplitude of dither in the flow control device signal, the second amplitude is different from the first amplitude.

12 . The method of claim 8 , wherein the test data includes:

a first rail pressure command and a first rail pressure feedback collected during the first test cycle, and

a second rail pressure command and a second rail pressure feedback collected during the second test cycle.

13 . The method of claim 12 , wherein determining whether the performance difference between the first test cycle and the second test cycle exceeds the predetermined threshold includes:

determining a first sum of absolute pressure error between the first rail pressure command and the first rail pressure feedback;

determining a second sum of absolute pressure error between the second rail pressure command and the second rail pressure feedback;

determining a difference between the first sum and the second sum;

determining whether the difference exceeds the predetermined threshold; and

detecting, in response to determining that the difference exceeds the predetermined threshold, the presence of high friction within the flow control device.

14 . The method of claim 13 , further comprising:

transmitting, in response to detecting the presence of high friction within the flow control device, a notification to a technician to replace the flow control device.

15 . A non-transitory computer-readable medium storing instructions for detecting a high friction within a flow control device of a fuel system, the instructions when executed by one or more processors of a computing device, cause the computing device to:

receive a service test sequence to execute a service test;

perform, in response to a receipt of the service test sequence, the service test to generate test data, the service test including a first test cycle with a first dither level and a second test cycle with a second dither level;

determine whether a performance difference of the flow control device between the first test cycle and the second test cycle exceeds a predetermined threshold based on the test data; and

detect, in response to a determination that the performance difference exceeds the predetermined threshold, a presence of high friction within the flow control device,

wherein the second dither level is different from the first dither level.

16 . The non-transitory computer-readable medium of claim 15 , wherein the instructions when executed by the one or more processors further cause the computing device to:

determine, in response to a receipt of the service test sequence, whether one or more enable conditions are satisfied to execute the service test; and

transmit, in response to a determination that the one or more enable conditions are not satisfied, a notification indicating that the service test cannot be executed,

wherein the notification further includes one or more remedial actions that can be performed to satisfy the one or more enable conditions.

17 . The non-transitory computer-readable medium of claim 15 , wherein to perform the service test includes to control the flow control device using a high frequency pulse-width modulation (PWM) signal with a superimposed low frequency dither waveform.

18 . The non-transitory computer-readable medium of claim 15 , wherein to perform the service test includes to:

perform the first test cycle by applying a first amplitude of dither in a flow control device signal, and

perform the second test cycle by apply a second amplitude of dither in the flow control device signal, the second amplitude is different from the first amplitude.

19 . The non-transitory computer-readable medium of claim 15 , wherein the test data includes:

a first rail pressure command and a first rail pressure feedback collected during the first test cycle, and

a second rail pressure command and a second rail pressure feedback collected during the second test cycle.

20 . The non-transitory computer-readable medium of claim 19 , wherein to determine whether the performance difference between the first test cycle and the second test cycle exceeds the predetermined threshold includes to:

determine a first sum of absolute pressure error between the first rail pressure command and the first rail pressure feedback;

determine a second sum of absolute pressure error between the second rail pressure command and the second rail pressure feedback;

determine a difference between the first sum and the second sum;

determining whether the difference exceeds the predetermined threshold; and

detect, in response to a determination that the difference exceeds the predetermined threshold, the presence of high friction within the flow control device.