Currently, there are stringent emission norms that regulate the level of pollutant emissions which all automotive engines must satisfy. In order to ensure that new internal combustion engines reach the level of emission established in these norms, researchers have studied the physical phenomena that happen in each part of the engine. One important phenomenon that has a great influence in both fuel consumption and pollutant emissions is the spray formed by the fuel injector. In this work, experiments were conducted in order to analyze the influence of test fluid temperature on atomization parameters of the spray formed by a single-hole port fuel injector (PFI). The n-heptane was used as test fluid at three temperatures (0, 30 and 60• C). The evaluations of droplet sizes, drop size distributions and drop velocities were performed by Phase Doppler Particle Analyzer (PDPA) technique. The measurements were taken 125 mm downstream from the injector tip along its axis with 300 kPa injection pressure. Results indicated that increasing the test fluid temperature induces a reduction in mean droplet diameters. This result was also observed in drop size distributions. Moreover, the increase in fuel temperature led to droplets with higher velocities.