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The TPS is a sensor that takes in voltage and then sends a corresponding voltage out to tell the ECU when to fire and how to open the injectors depending on the amount the throttle valve is open. If the TPS is giving the wrong information the engine simply won't run correctly. keep in mind the more the throttle opens the more fuel and spark advance. If the TPS says wide open it will advance the timing but at the same time add more fuel yet the air will not correspond so the engine boggs. If the TPS fails the engine may go into a Guardian mode but you won't ruin the engine.
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