1.8L and 2.0L engines
The crankshaft position (CKP) sensor signal is the basis for ignition timing calculations. The alternating voltage signal from the CKP sensor is digitized by the powertrain control module (PCM). This digitized signal is then used to position the closing time of the primary circuit of the ignition coil.
Ignition angle is determined by the PCM in response to engine operating conditions. Once ignition angle has been determined, the PCM interrupts the current to the primary circuit of the ignition coil thus triggering the ignition spark which is supplied to the cylinders through the spark plug wires and spark plugs.
The ignition coils are triggered by the PCM in pairs (cylinders 1 and 4 and cylinders 2 and 3) sending one ignition spark to the firing cylinder and one ignition spark to the corresponding cylinder on the exhaust stroke.
