P0464 Code: Fuel Level Sensor Circuit Intermittent

What the P0464 code means

The fuel level sender reports how much fuel is in the tank. Besides the gauge needle on the dash, the computer uses it to decide when to run the EVAP test (normally with the tank between 15 and 85 percent full) and to detect misfires caused by running out of fuel.

The sender is a variable resistor moved by a float, and the computer (or the instrument cluster) measures its resistance or the resulting voltage. The P0464 code flags intermittent dropouts, and those almost always come from a bad contact or a damaged wire.

With the level signal failing, the needle may stay fixed or move at random, and the EVAP test does not run. Wear on the resistive track of the sender is very common as the years go by, and the needle jumps at certain levels. Look up the sensor guide to see how it is tested.

Intermittent faults are found by reproducing them. With the engine running and the scan tool in graph mode, move the wiring harness section by section, tap the connector gently and, if needed, warm the area with a hair dryer or wet the connector with a spray bottle. The point where the reading jumps is the point of the fault.

P0464 code symptoms

• Check engine light on.
• Incorrect fuel gauge reading and an incomplete EVAP test.
• Emissions monitor incomplete, so the vehicle cannot pass inspection.
• Often there are no other driving symptoms.

Likely causes of the P0464 code

1. Bad contact in the connector from loose or backed-out pins.
2. Wire broken inside its insulation from vibration.
3. Connector exposed to water on sensors mounted under the vehicle.
4. Sender with an intermittent fault, often temperature related.

How to diagnose the P0464 code step by step

1. Read the sensor value on the scan tool and compare it with what you expect.
2. Inspect the connector for corrosion, water or loose pins.
3. Check the reference and ground and measure the sender resistance with the connector unplugged.
4. Measure the signal with the connector plugged in and see whether it changes with conditions.
5. Do a wiggle test on the wiring.
6. Check continuity to the computer.
7. Add a known amount of fuel and check whether the needle moves in proportion.
8. Measure the sender resistance at several levels at the fuel pump connector.

How to fix the P0464 code

• Repair the connector or the wiring.
• Replace the sender if the tests confirm it is bad.
• Correct the real condition if there is one (a leak or a blockage).
• Clear the codes and complete a drive cycle so the monitor runs.

Technical reference data

• Variable resistance (for example 10 ohms full and 180 ohms empty, or the other way around, depending on the manufacturer).
• Approximate values only: check the manufacturer data for your engine.

Brand-specific notes

On many vehicles the fuel level sender is sold together with the fuel pump module, and on others it is sold separately. Check which applies to yours before you price the repair.

A gauge that jumps only at certain fill levels points to a worn track in the sender, while one that drops out at random points to the connector or wiring.

Frequently asked questions about P0464