ORVR System - Premature Shut off during refueling
Group: FUEL SYSTEMNumber: 97-30-005
Date: DECEMBER, 1997
Model: 1998 ELANTRA & TIBURON
Subject
ON-BOARD REFUELING VAPOR RECOVERY (ORVR)
DESCRIPTION:
1998 MY Tiburons and Elantras are equipped with new federally mandated automobile-based controls for refueling emissions, On board Refueling Vapor Recovery (ORVR).
ORVR is a vehicle emission control system that captures fuel vapors from the vehicle gas tank during refueling. During refueling, the new, smaller diameter filler neck seals to the outside diameter of the fuel nozzle. When gasoline is dispensed, it forms a positive pressure in the fuel tank headspace which forces the headspace vapors into the charcoal canister. When the engine is in operation, stored gasoline vapors are drawn into the engine intake manifold and are burned.
ORVR systems are designed to be transparent to the customer. Most new vehicle owners may not notice any difference in the vehicle. However, some may experience premature gas pump shut off conditions during refueling. A very small percentage of gas pump nozzles won't fill the new car's gas tanks. Fuel nozzle manufacturers/ suppliers have identified the condition on certain nozzle models and are in the process of replacing these units.