The applications of ultra wideband (UWB) technologies in commercial vehicles wireless networked control systems (NCS) are attracting attention recently. The transmitted reference (TR) signaling, along with an autocorrelation receiver (AcR), is used for UWB intra-vehicle communication systems. In this paper, we analyze the performance of UWB intra-vehicle NCS with TR signaling under different time-bandwidth products and different numbers of transmitted pulses per symbol conditions. The bit-error probability (BEP) performance of this system is estimated based on the Gaussian approximation and the sampling expansion methods. Through Monte Carlo simulations, we investigate the limitation of the validity of the conventional Gaussian approximation and the sampling expansion methods for the intra-vehicle NCS.