Eaton eVaptive™ Electronic Fuel Tank Venting System Reduces Cost, Complexity

Date: 2017/3/21

SOUTHFIELD, Mich. … Power management company Eaton announced its new eVaptive™ electronically controlled fuel tank vapor venting system that can be optimized for any vehicle platform, eliminating the need for automakers to design unique venting systems for different vehicles.

The eVaptive system uses software to control the transmission of fuel vapors to a charcoal canister while keeping liquid fuel confined to the fuel tank. For any given fuel tank application, the system can be optimized for all driving situations as well as stationary and refueling modes. The hardware is a “one-size-fits-all” unit that can be programmed to fit any vehicle platform.

“This new technology is an example of the advanced engineering capabilities of Eaton as we look to provide customers with solutions that not only provide a single packaging option but also the flexibility to customize the system based on the specific vehicle design,” said Deborah Kullman, vice president, general manager, Chassis Driveline Controls, Eaton Vehicle Group. “As the industry moves from traditional mechanical to electronic solutions, Eaton is leading the way with technologies such as eVaptive.”

In a traditional fuel tank design, optimal vapor venting positions are determined at the top of the tank where vapors accumulate. Once determined, Eaton’s eVaptive system vent points can then be opened and closed as needed for optimized venting via an actuator system. Any liquid fuel that enters the vent tubes is routed to a central liquid trap where it is drained back into the fuel tank. Once the vapor and the errant fuel are separated in the liquid trap, the vapor is routed to the charcoal canister for adsorption.

The actuator system is controlled by a computer algorithm that minimizes fuel carryover to the interior liquid trap in all situations and controls the fuel level during refueling. It also can be used to mitigate the spillover that sometimes occurs when filling a tank to the top.

Other benefits of the eVaptive system include:  

  • Reduced complexity and cost by allowing customers to use one set of hardware across all vehicle lines and tank variants;
  • Prevents liquid from leaving the tank when driving while still venting vapors;
  • Reduces validation cycles and development time;
  • Adaptive learning optimizes the eVaptive system venting algorithm;
  • Maintains overall lower tank pressures in dynamic situations and at high-fuel levels;
  • eVaptive system is not impacted by the shut-off height of mechanical valves;
  • Enables On-Board Diagnostics II (OBDII) leak detection to ensure no hydrocarbons are escaping into the atmosphere;
  • System can replace the current Fuel Tank Isolation Valve (FTIV); and,
  • eVaptive system has the ability to customize the pressure relief of the fuel tank needed just prior to a refueling event on plug-in hybrid electric vehicle applications.


Eaton’s eVaptive system is currently undergoing testing with a global automaker.

Eaton is a power management company with 2016 sales of $19.7 billion. Eaton provides energy-efficient solutions that help our customers effectively manage electrical, hydraulic and mechanical power more efficiently, safely and sustainably. Eaton has approximately 95,000 employees and sells products to customers in more than 175 countries. For more information, visit