Ignition, DIS and programmed ignition

1. Ignition Systems
page 11

2. Distributorless Ignition

3. Distributorless ignition is used
extensively today by many
manufacturers

4. Instead of using a
……………………, a special coil
is utilized.
Distributor

5. The basic principle is that of the
‘lost spark’.
The distribution of the spark is
achieved by two double ended
coils which are fired
…………………… by an ECU.Alternately

6. When one of the coils is fired, a
spark is delivered to two
cylinders, either 1 and 4, or 2
and 3. The spark delivered to
the cylinder on compression will
ignite as normal.

7. The cylinder on the exhaust
stroke will also have a spark
delivered to the spark plug, but
this will have ………………… to
the running of the engine, the
spark is ………………
No effect
Wasted

8. Label the following components
DIS Coil
Crank
speed and
position
sensor
ECU with
built in MAP
sensor
Coolant
temperature
sensor

9. Programmed Ignition

10. Another variation of controlling
the ignition is a system called
programmed ignition.
Programmed ignition systems
are also operated by a computer
(ECU).

11. This system has several
………………… over the basic
distributor systems.
Advantages

12. The ……………… timing can be
altered to accurately match a
wide range of engine …………
and ………… conditions, which
are stored inside the memory of
the ………… using what is
known as ‘maps’.
Ignition
Speed
Load
ECU

13. The illustration below shows the
components used in a programmed ignition
system; name the numbered components.
1 – ECU
2 – coolant temp.
sensor
3 – knock sensor
4 – crank sensor
5 – coil
6 – ignition switch
7 – distributor

14. Questions
1. What is different about the DIS coil?
2. What happens to the wasted spark?
3. What is the reluctor ring?
4. What is the function of the knock sensor?
5. What is the function of the crankshaft
sensor?
6. What ignition component is replaced by
the DIS coil?.

15. Answers
1. It produces two sparks at the same time
2. The wasted spark is introduced into the
cylinder on the exhaust stroke, it is wasted
3. A reluctor ring is what excites an inductive
sensor
4. The knock sensor, senses knocks in the
cylinder caused by pinking, then signals the
ECU to retard the timing
5. Tells the ECU the speed and position of the
crankshaft
6. The distributor