Powertrain, generic · Auxiliary emission controls

P0464 Fuel Level Sensor A Circuit Intermittent

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

The fuel level sensor is a float on a resistor track in the tank unit. It is no emission part, but other monitors depend on it – the EVAP leak tests, for example, need at least 15 % fuel – so CARB requires it to be monitored and the usual exemption from the warning lamp does not apply. At GM, P0464 is a by-product of the engine-off EVAP leak test: a jump in fuel level with the vent valve closed counts as possible refuelling and aborts the test; if a following check finds no real refuelling, the jump is counted as an intermittent sensor signal (change above 10 % not stable for 30 s, 2 of 3 samples). GM sets the code with MIL on the first trip, because otherwise the leak monitor would be defeated permanently. Ford does not use P0464 and reports jumps as P0461.

Likely causes

Loose contact or corrosion at the tank connector or sensor terminal
Worn spots on the resistor track (wiper skipping)
Chafed wire with intermittent contact
Car parked on a steep slope or fuel sloshing after switch-off

Symptoms

  • Check engine light on (GM after one trip)
  • Fuel gauge occasionally jumps
  • EVAP readiness not set

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel level sensor afuel tank unitsensor wiringengine control module

Related codes

P0461P0462P0463P0442P0456P2069

References: gsi.ext.gm.com, saabwisonline.com, law.cornell.edu.