Does this blend vapour pressure increase, create car engine functioning problems?
In the US, maximum petrol vapour pressure is 62.055 kPa. Legislation allows blends of this petrol with up to 10% bioethanol, which increases petrol base vapour pressure in summer to 1 psi (6.89 kPa) maximum. The US experience demonstrates there are no functioning or starting problems in cars operating with these petrol-bioethanol blends. The EU Fuel Quality Directive currently establishes a maximum base petrol pressure of 60 kPa. Revision of this Directive –currently under discussion in European institutions – the European Commission has proposed authorising a maximum summer petrol-bioethanol blend vapour pressure of up to 68 kPa, assuming under these conditions the cars maintain all their performances.
