In at least some implementations, a charge forming device includes a main body having a throttle bore, a throttle valve, a housing and a circuit board including a throttle position sensor and a pressure sensor. The throttle valve is received at least partially within the valve bore, is rotatable between an idle position and a second position, and includes a magnet that is rotated when the throttle valve rotates. The housing is carried by the main body, and the circuit board is carried by the housing. A signal path is defined leading from the pressure sensor to a pressure source, the signal path includes a liquid collection area located below a gaseous area with respect to gravity.