The research concerns the flash boiling of fuels injected into combustion engines. This is the phenomenon where an injected fuel jet flash vaporizes due to a sudden reduction in the injection pressure in the combustion environment. The cavitation bubbles that form, grow and can expand the jet resulting in interference of jets for multi-port injectors. The problem is controlled by bubble nucleation and growth phenomenon in the fuel jet. The initial conditions that trigger the process, namely superheating of the jets for a range of fuel systems including single component systems, and surrogates for petroleum-based fuels were investigated. The work is primarily experimental and focuses on the bubble nucleation phenomenon for miscible mixture systems. The experimental apparatus uses a bubble column to simulate a droplet going through a rising temperature gradient beyond its boiling point until nucleation is observed. Although primarily experimental, computations were also performed to compare the experimental results to what theory would dictate. Results from the experiments were then processed and the superheat limits were compared to theoretical results obtained using both the thermodynamic and kinetic limit of superheat and general agreement was observed.