A mobile communication system modulates input data with a specific size into an OFDM symbol and transmits the OFDM symbol through an antenna. According to another aspect, a method comprises restricting deactivation of fuel injection during deceleration operations under all wheel drive, or 4\xd74 low gear operation; and disabling the fuel injection during at least some deceleration operation under other conditions. The symmetrical pumping elements have ending points that stop short of the seal edge of the seal.