303-07-219
Engine Ignition
303-07-219
DESCRIPTION AND OPERATION
E6679 EN
07/2001 2002 Bantam
Engine Ignition
The ignition system is of the distributor less type.
The crankshaft position sensor (CKP) signal is
the basis for ignition timing calculations. The
camshaft position (CMP) sensor signal is
required only during starting as when the engine
is running, the profile ignition pick-up (PIP) signal
is used. The alternating voltage signal from the
CKP sensor is digitized by the powertrain control
module (PCM). This digitized signal is then used
to time the closing of the ignition coils primary
circuits.
Ignition timing is determined by the PCM in
response to engine operating conditions. Once
ignition timing has been determined, the PCM
interrupts the current to the primary circuits of the
ignition coils therefore triggering ignition sparks
which are supplied to the cylinders through the
spark plug wires and spark plugs.
The ignition coils are triggered by the PCM in
pairs, cylinders No.1 and No. 4 and cylinders No.
2 and No. 3, sending an ignition spark to the
firing cylinder and to the corresponding cylinder
on the exhaust stroke. Having an ignition spark
on the exhaust strokes makes sure that any un-
burnt fuel left in the cylinder is ignited to provide
cleaner exhaust emissions.
