The Effect of Increasing Fuel Volatility on Exhaust Emissions 860533
Vehicle tests showed that exhaust HC and CO were significantly increased with a high volatility (12.5 psi Reid vapor pressure) Indolene plus butane blended fuel when compared to Indolene (9.0 psi RVP) fuel. The HC and CO increases were greater for a vehicle without closed-loop fuel control than for three closed-loop vehicles. Testing indicated that the exhaust emissions increases may have resulted from the higher loading of the evaporative canister with the high RVP fuel. Exhaust NOX emissions were not affected by the change in fuel volatility.