Flex Fuel Sensor - AC Delco
AC Delco

Flex Fuel Sensor - AC Delco

$105.00 USD
$105.00 USD

This inline fuel sensor is designed to measure the ethanol to gasoline ratio in real time. By sending a frequency based signal to the ECU it allows the engine management system to automatically adjust fueling and ignition for blends ranging from pure gasoline to E85.

Physical Specs

  • Part Number: 13577379

  • Weight: ~0.28 lb. (≈128 g)

  • Size: 4.4 in long × 3.5 in wide × 1.6 in tall

  • Housing/Ports: Fuel flows through the sensor body which uses quick connect style fittings (commonly 3/8 in)

  • Connector: 3 pin oval female style with blade type terminals

Electrical and Signal

  • Wiring: Three connections: 12V supply ground and signal output

  • Output Type: Digital square wave frequency proportional to ethanol concentration

  • Typical Range: ~50 Hz (gasoline) up to ~150 Hz (E85)

  • Fault Indication: Frequencies in the 180 to 190 Hz range can signal contamination or a sensor issue

  • Signal Handling: Most ECUs provide a 5V pull up with the sensor pulling the signal to ground in pulses

Functionality

  • All of the vehicles fuel passes through the sensor before reaching the injectors so the composition reading reflects actual fuel mix

  • The internal processor not only reports ethanol percentage but also monitors for abnormal fuel conditions

  • Data from the sensor enables adaptive engine control strategies like timing and fueling adjustments for safe and efficient operation across different fuel blends