Quote:
Originally Posted by aerohead
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The vernier-rheostat inside the throttle-position-sensor, and its variable resistance signal is a vital component of, and the CPU hasn't a clue what's happening without it's signal.
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1. No car uses a rheostat as the throttle position sensor (TPS). They use a potentiometer. Different device, three wires versus two, with a different output (voltage versus current). There is no 'varying resistance signal', there is a varying voltage signal.
2. In cars without electronic throttle, and excluding the earliest L-Jetronic systems that used a full-load throttle switch and the 'carby-like' Bosch Mono-Jetronic system, the TPS is not used to indicate load to the Electronic Control Unit (ECU).
3. Engine load is determined by either:
- the combination of a MAP (Manifold Absolute Pressure), engine RPM and look-up tables that correlate these with engine volumetric efficiency
or
- the output of the airflow meter
The main function of the TPS is to control transients - eg fuel enrichment / enleanment on throttle increase / decrease, and the same for ignition timing advance / retard.
Note that in throttle stop testing, the throttle is not moved.
As I said, you obviously don't have much understanding of engine management systems. That's OK, but it makes criticism of the throttle stop method based on your misunderstandings pretty problematic.