Reason for this post is that im currently looking at my throttle position sensor to see if it requires cleaning and an idle relearn. I have noticed that there are a few different throttle PIDS.
All very involved in a drive by wire system, just remember the driver tells the engine computer how much throttle he wants and the engine computer decides how much to open the throttle in response.
The desired throttle position is the the engine computer wants the throttle butterfly to move to.
The actual throttle position is exactly what is says the actual percentage opening of throttle butterfly
Also in a drive by wire system gasoline (or diesel) engine the accelerator pedal as two position sensor as a fail safe sanity check. The two senor outputs work in opposite directions 0-5v and 5-0v.
The throttle butterfly position sensor on drive by wire throttlebody has similar 0-5v and 5-0v sensor outputs.
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(Walter Bishop Fringe TV show)
It's kinda confusing. :silly: The way I understand it, Absolute Throttle is the unlearned value of the TPS sensor. It's always gonna read something, even with the throttle completely closed.
Relative Throttle is the throttle position compared to the learned closed position. As in, if 9% Absolute is with the throttle fully closed, then Relative will read 0% in the same position.
How can you use these values while trouble shooting? I never really know what to do with them.
While we are on the topic of PIDs, what the heck is STFT sensor 1? I understand bank 1 but see sensor 1 sometimes too, maybe as a high percentage like 99%.
The stft sensor pid shows the grade of authority this specific sensor has on the fueltrim. But be aware that often times a 99ish percentage reading _ especially for the post cat O2 sensor - just means NO fuel trim correction from this sensor!
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I bet to differ, my system is electronic throttle body which has the TPS embedded in it, not drive by wire but i have the data pids OP mentioned which outputs values.
