Abstract: A system and method for improving exhaust gas recirculation performance is provided to induce improved exhaust gas recirculation flow during engine operating transients, including transients in which exhaust gas flow conditions are unfavorable. The apparatus includes an exhaust line including a mechatronic exhaust brake valve, an intake system including a PBS compressed air injection system, an exhaust gas recirculation passage between the exhaust and intake lines, and a controller which coordinates operation of the PBS and MEB. The controller is programmed to command the MEB to close for a period before the compressed air injection is initiated so as to build exhaust line backpressure pressure and maintain a desired pressure differential across the EGR passage so that recirculated exhaust gas flow continues to enter the intake during to PBS injection event to suppress formation of undesired excess NOx, particulate and other emissions.

Abstract: A roll stability control system for a pneumatically operated vehicle brake system is implemented using simpler ABS hardware rather than more complex EBS hardware. For each brake chamber or channel, two 3/2 solenoid controlled valves are used. An ECU is operative to control the solenoids. The ECU is preferably operative to provide a selected delivery pressure to the brake chamber without measurement of delivery pressure to the brake chamber. Supply air is provided at a known pressure to a first solenoid controlled valve that is associated with the brake chamber; the amount of time of energization and de-energization of the first valve that is needed to provide an output therefrom of a given pressure, is calculated; and the first valve is energized and de-energized for the calculated times, thereby to cause a low-pressure test pulse to be provided to the brake chamber.