I often find myself working with unkown/proto engine, and i go trough the manual process of logging with my picoscope crank signa, can signal ( with the VVT disconnected or disabled) and the cyclinder pressure in the cylinder one.
for measuring the cylinder pressure i simply use a pressure sensor and a compression testing hose.
there are already some tool available like this:
If we can add in the scope the pressure signal, or, as seems more of a digital, just the peak signal reference vs the rpm, the calculation of the offset will be a breeze. Ideally we could also add a feature for the self calibration of the TDC offset using a specific input just for this test, like the map input.
I am not so sure about automatic calibration, but overall, it’s a neat trick.
Any issues with sensor readings will render the auto calibration invalid.
So there would have to be a way to confirm it manually.
With that in mind, it would be best to have the voltage of analog input 1 plotted on our scope.
Then you could measure the offset by clicking and dragging the cursor on the scope.
Digital input alone is not very useful for that task. For the digital input to switch between 0 and 1, the signal needs to go over/under the threshold. However, you won’t know what the threshold is without examining the analog value. You could find the threshold by starting with a high value and lowering it step by step until you get a reaction, but that is cumbersome and unnecessary.
We had a request like that some time ago.
We will increase the priority for it, but it’s not a straightforward task.
Some technical difficulties need to be addressed to make it work.
i was able to acheive a rough check by logging directly the analog input value and compare with the digital input 1 and 2 (crank and camshaft). Will give me the rigth phase and close enough to the right tooth. The with the strobo light we can correct the offset. so probably we can do something similar without the oscilloscope. like a Phase calculator in Data Master could help as well
