If a throttle position sensor (TPS) is fixed around 4.5 volts, what could it cause?

When a throttle position sensor (TPS) is fixed at a voltage level of around 4.5 volts, it typically indicates that the sensor is signaling the engine control unit (ECU) that the throttle is nearly or fully open. This improper reading can lead to incorrect air-fuel mixture adjustments, affecting engine operation.

In this situation, the condition most closely associated with a constant high voltage signal from the TPS is "clear flood mode." When the TPS indicates a near-wide-open throttle position, the ECU might interpret this as a need to limit fuel delivery to prevent flooding when starting the engine. The engine may enter a clear flood mode to allow starting under these conditions, which entails cutting fuel flow while trying to start the engine.

While high idle and rough idle are common symptoms of various throttle position sensor issues, they are not the primary cause resulting from a TPS fixed at around 4.5 volts in this particular context. The focus here on clear flood mode effectively highlights the significance of throttle position readings and their impact on engine performance and starting conditions.