ORVR (On-Board Refueling Vapor Recovery)

Any vehicle fitted with the LDP is also ORVR compliant. The ORVR system addresses recovering fuel vapor which is released during refueling. Previously, fuel vapors were vented from the tank venting line back to the filler neck and in many states reclaimed by a vacuum receiver on the filling station's fuel pump nozzle.

ORVR provides a means to "capture" these hydrocarbon vapors resulting from the rush of fuel into the tank during fuel filling. The following changes were installed to achieve this:

- Re-routing the previous tank vent hose from the filler neck to the liquid/vapor separator. This hose was also enlarged to accommodate the increased "vapor flow" being introduced into the liquid vapor separator.
- Enlarging the rollover valve and the hose from the liquid/vapor separator to the charcoal canister.
- Modified filler neck which allows a higher flow rate.
- Modifications to the fuel tank to form a liquid seal during refueling - forcing vapors to the liquid/vapor separator.

When refueling, the pressure of the fuel entering the tank will force the hydrocarbon vapors through the tank vent line to the liquid/vapor separator, through the rollover valve and into the charcoal canister. The hydrocarbons are stored in the charcoal canister; and the system can then "breathe" through the LDP pump and the air filter.

The small hose at the fuel filler neck is still required to check for leaks at the filler cap.