After making all the necessary connections, the procedure for the gasoline engine is as follows. Start the engine and wait for the idle speed to stabilize. Start the recording in the USB oscilloscope program window. After a few seconds, smoothly increase the engine speed to 3000 RPMs. Sharply release the accelerator pedal and wait for the idle speed to stabilize. Sharply press the accelerator pedal and after reaching 3000, 4000 RPMs, turn off the engine, while keeping the accelerator pedal fully pressed until the engine stops completely. It is important that the throttle valve remains fully open. Stop signal recording. On modern cars, instead of a mechanical connection between the accelerator pedal and the throttle, an electronic pedal and an electronic throttle actuator are used. When performing a CSS test on such cars, during the last step of the measurement, the throttle valve may close despite the fact that the accelerator pedal was still pressed. In this case, the CSS test will not be performed in full, namely, the dynamic compression in the engine cylinders will not be measured. If the task is to check the compression using the CSS test, then in order to turn off the engine, instead of turning off the ignition, you will need to disable the power supply circuit of the fuel injectors. The best way to do this is with a remote switch. For safety, the switch should be equipped with a fuse. Find the location of the desired fuse in the car, and instead of it, connect to the remote switch. In this case, at the end of the test, you will need to turn off the engine not in the usual way, but by turning off the button on the body of the remote fuse switch. Note that in some cases, this fuse also powers other components. On some cars equipped with a digital output signal type crankshaft position sensor, at the last stage of measurement, immediately after turning off the ignition at high RPMs, the signal from the crankshaft position sensor may disappear even before the engine is completely stopped. In this case, the CSS test will not be performed in full, the dynamic compression in the engine cylinders will not be measured. If the task is to check the compression using the CSS test, then you will have to use the remote fuse switch to turn off the engine. On vehicles where it is difficult or impossible to connect to the signal wire of the crankshaft position sensor, instead of the signal from the standard crankshaft position sensor, you can record the signal from the external crankshaft position sensor. The most convenient way to do this is to use an external optical laser crankshaft sensor. During the test, the ray of this sensor should be directed to the optical marks, previously applied with white paint on the crankshaft pulley, and simulating the teeth of the reluctant wheel. For diesel engines, the procedure for the CSS test is different from the procedure for the gasoline engine test. After making all the necessary connections, the procedure for the diesel engine is as follows. Start the engine and wait for the idle speed to stabilize. Start recording in the USB oscilloscope program window. After a few seconds, smoothly increase the engine speed to 3000 RPM. Sharply release the accelerator pedal and wait for the idle speed to stabilize. Sharply press the accelerator pedal and after reaching 3000, 4000 RPM, turn off the engine by turning off the ignition. The throttle valve will automatically cut off the air flow into the intake manifold. Stop signal recording. If the intake manifold is not equipped with a throttle valve to shut off the engine at the last stage of measurement, the air flow entering the intake track should be shut off. It is important to keep it closed until the engine comes to a complete stop. As soon as the recording of signals is stopped, the USB oscilloscope software automatically saves them to a temporary file and immediately displays these signals on the screen. If you think that you may need these signals again, it would be better to immediately save them to a file. To do this, call the file, save file menu, and specify where and under what name to save it. But the analysis of signals can be started without first saving them to a file, since the scripts can also work with a temporary file. This means that you can call the analysis, execute script menu immediately after you stop recording. At the moment of starting the analysis, the so-called configuration window will be displayed. In this window, it is necessary to specify the parameters of the tested vehicle, the main of which is firing order. If the synchronization signal was not taken from the first cylinder, then in this case such parameter is, number of synchronization cylinder should be correctly specified. All parameters entered in the configuration window can be embedded in the waveform file. Due to this, when you run the analysis of this file again, the configuration window will automatically be correctly configured. To save these parameters, just call the file, save file menu, and confirm yes. Or you can simply select yes in the, do you want to save the current file or the changes you made, dialogue when closing this file. I would like to draw your attention to the fact that in cases where the script, for one reason or another, fails to analyze the recorded signals. They should always be saved to a file posted on the forum in the script development topic. This practice helps us to collect materials needed to further improve the script's algorithms.