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Internal Combustion engines with multi-point, or sequential, fuel injection have a fuel injector for each cylinder, usually located so that they spray right at the intake valve. While in a fully warmed-up engine, fuel droplets vaporize before entering the combustion chamber, at cold start, a significant proportion of the injected gasoline deposits on the intake port and valve surfaces. The result is a deterioration of mixture homogeneity, decreased metering accuracy and increased hydrocarbon emissions. A better control of mixture preparation at cold start conditions can be achieved if the interaction between the gasoline spray and the time-varying liquid film which forms during the period of injection can be accurately predicted. The work reported here considers part of an experimental study performed with that objective in a purposed built experiment considering a simplified geometry.Droplet characteristics measured with a PDA system in the vicinity of the impact surface, prior and right after the impact, are used to infer about the transient spray-wall interaction mechanisms when a liquid film forms. Conservation laws allow to derive the fractions (α θ ) of mass, momentum and energy from the spray prior to impact that are transferred to/from the liquid film. Most of the inflowing mass deposits within the core of the spray and transfers momentum to the liquid film in the radial direction, influencing the velocity and direction of secondary droplets formed at impingement. The use of α θ , together with the mass flux ratio of outgoing to inflowing droplets in existing empirical correlations to predict the impingement outcome, is shown to improve prediction of flux ratios, either of number, momentum or energy. These fractions are suggested as a simple way of including the influence of the liquid film in spray/wall interaction and their modelling is the scope of future work. LFS SS ST LFS SS ST