複選題74. 一多點噴射汽油引擎怠速運轉不穩，但當轉速增加時則運轉平穩，進行檢修之排放氣體檢測數據如圖所示，下列何者為較不可能之故障原因？(A)A secondary ignition wire shorted to ground(B)A parti ally clogged fuel injector(C)An EGR valve pintle that does not fully close(D)A leaking intake manifol d gasket。