Abstract: A system for an engine, comprising of a cylinder located in the engine; a first injector for injecting a first fuel into said cylinder; a second injector for injecting a second fuel into said cylinder; and a controller configured to vary an amount of said first and second fuel injection during engine operation based on operating conditions, where amounts of variation of said first and second fuels are set to maintain desired engine output and provide a substantially stoichiometric mixture.

Abstract: A system for an engine of a vehicle, comprising of a cylinder of the engine; a first injector configured to inject a first substance to said cylinder; a second injector configured to inject a second substance to said cylinder; and a controller configured to perform injection from said first and second injector in response to a number of combustion events from an engine start.

Abstract: A system is described using a fuel quality sensor for controlling various aspects of engine operation. In particular, an acoustic wave sensor is utilized to measure viscosity and density of gasoline fuels. This measurement is utilized to predict engine combustion quality during an engine start. Based on the prediction, the method adjusts engine operating parameters (such as fuel injection amount and ignition timing) to achieve improved vehicle driveability and engine combustion.

Abstract: A system is described using a fuel quality sensor or an estimate of fuel volatility for controlling various aspects of engine operation. For example, improved fuel tank leak detection may be achieved using an estimate of fuel volatility obtained from fuel purging operation.