It is beneficial to know the signs of a failing glow plug so that you can avoid major problems. And, this graphical presentation can be useful for you in this regard. So, please go through it.
9. The heat energy
generated due to this
process accomplishes
the following tasks;
• Facilitates combustion of air
and fuel inside the cylinder.
• Helps to start the engine-
especially in colder weather
conditions.
• Makes the engine an
efficient source of torque.