P0464

P0464 means the fuel level sensor circuit is reporting an intermittent fault — the ECU is seeing the sender voltage glitch outside its expected range (typically 0.5-4.5V scaled across the 16-270 ohm float-resistance sweep, full-to-empty) and then come back into range on its own. Cheapest-first diagnostic ladder: (1) Drop the rear seat or access cover and reseat the fuel-pump-module connector — a 5-minute job that fixes maybe a third of P0464 tickets, especially on vehicles that have been off-road or salt-belt-driven where contact corrosion is the silent killer. (2) Scan-tool the live fuel-level percentage and watch it while a helper rocks the vehicle side to side; a healthy sender sweeps smoothly between values, a dying rheostat element jumps in steps or drops to 0% momentarily. (3) Back-probe the sender signal wire at the connector with a meter on Hz/duty cycle (for analog senders, read DC volts) — at half tank you should see roughly mid-range (around 2.5V or ~140 ohms for a typical 16-270 ohm sender); a wildly erratic reading with the float held steady means the resistive track in the sender is worn through. The expensive-misdiagnosis caveat: don't drop a fuel tank to replace the pump module on a P0464 until you've ohmed the sender and confirmed the harness from the tank-top connector forward — half of intermittent P0464 codes are a corroded body-side connector or a chewed wire under the rear seat, not the $300-500 pump-and-sender assembly.

Vehicle-specific patterns: 2004-2010 Ford F-150/Expedition and 2007-2014 Ford Escape commonly throw P0464 from the well-known fuel-pump-module top-plate connector corroding — the harness sits under the rear seat or pickup bed and water/salt gets in; cleaning pins with DeoxIT often clears it before parts swap. 2003-2008 GM trucks (Silverado/Sierra/Tahoe/Yukon) with the in-tank sender frequently throw P0464 from sulfur-contaminated fuel etching the resistive strip on the sender card — GM revised the sender material around 2007 and replacement parts use the updated alloy; expect 60k-90k miles of life on the original. 2005-2010 Chrysler 300/Charger/Magnum and 2007-2012 Jeep Wrangler JK throw P0464 from a known fuel-level sender failure inside the module — Mopar sells the sender separately from the pump, which saves money if the pump still flows pressure. 2008-2013 Toyota Highlander/Sienna throw P0464 from harness chafe where the body harness drops into the tank cavity. Sender-only replacement runs $80-220 in parts; full pump-and-sender module is $300-600 parts, $450-900 installed. Estimated repair: $30 (connector clean) to $900 (full module on a Sienna).