While the spark-ignition (SI) engine technology migrates towards challenging combustion regimes (dilute and boosted operation), advanced ignition technologies generating non-equilibrium types of plasma have continued to receive significant attention from the automotive industry as a potential replacement for conventional spark-plugs. However there are no models currently that can describe the non-thermal plasma ignition process in the computational fluid dynamics (CFD) codes that are widely used in the engine multi-dimensional modeling community. A key question for the engine modelers that are trying to describe the non-equilibrium ignition physics concerns the characteristics of the non-equilibrium plasma. A key challenge is represented by the plasma formation timescale (nanoseconds) that can hardly be resolved within a full engine cycle (milliseconds) simulation. This paper reports on multi-dimensional modeling of the characteristics of plasma generated by a nanopulsed high-voltage discharge in a pin-to-pin electrode configuration, and evaluates the effects of ambient conditions (pressure, temperature, mixture composition) on the post-discharge results. It is shown that a nanopulsed delivery can result in a low temperature plasma or a mode transition to an arc-like event depending on the mixture properties in the gap between the two electrodes. It is also shown that the numerical results closely match the experimental observations and, even more importantly, agree with recent experiments on the same identical geometry, from both a qualitative and quantitative standpoint. As a result, the high-fidelity modeling effort described in this paper can be used as a key capability in understanding the true nature of non-equilibrium plasmas for automotive applications and lead to the future implementation of dedicated models for non-conventional ignition technologies.