P0464 indicates that the fuel level sensor circuit is sending an intermittent or erratic signal to the engine control module. This causes the fuel gauge to behave unpredictably and triggers the Check Engine Light.
The sensor inside the fuel tank develops an open circuit, short, or noisy output as the float moves, causing intermittent signal loss.
Wires between the sensor and the PCM can chafed, corroded connectors, or loose pins that interrupt the signal intermittently.
A weak or corroded ground at the tank or chassis can cause the sensor voltage to drop out intermittently.
Mechanical binding of the float prevents smooth movement, producing erratic resistance changes as fuel level changes.
Very rare; the PCM's fuel level sensor input circuit can fail, but this is considered only after sensor and wiring are verified good.
No. PCM failure is uncommon for this code; most cases are caused by the fuel level sensor, its wiring, or a ground issue. Replace the PCM only after those components have been tested and found good.
You can drive, but the fuel gauge may be unreliable. Monitor your fuel level manually to avoid running out of fuel unexpectedly.
With the connector unplugged, measure resistance across the sensor terminals while moving the float arm through its range. The resistance should change smoothly and match the manufacturer’s specifications.
Only if the fuel level sensor is integrated into the pump module and deemed faulty. Many vehicles allow the sender unit to be serviced or replaced separately.