Page 106 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

The ECU can increase or decrease the amount of oxygen in the exhaust by adjusting the air-to-fuel ratio. The
system ensures that the engine runs at close to the stoichiometric point in normal driving conditions. It also
ensures that there is always sufficient oxygen in the exhaust system to allow the oxidization catalyst to deal with
unburned hydrocarbons and carbon monoxide.

Closed loop control system
Control system in which the output has an effect on the input quantity in such a manner that the input quantity will
adjust itself based on the output generated is called closed loop control system in this way closed loop control
system is called automatic control system.

Importance of maintenance, diagnosis and Servicing

exhaust systems

Objectives: At the end of this lesson you shall be able to
• demonstrate maintenance, diagnosis and Servicing of exhaust systems.

Servicing of exhaust system
improve Fuel Efficiency
Keeping your vehicle’s exhaust system in tip-top condition can help you improve fuel efficiency. After all, who
doesn’t love making their car more fuel efficient? If the components of your vehicle’s exhaust system are failing
for some reason, you may notice that your car is getting poor engine combustion and gas mileage. For example,
a clogged catalytic converter can cause a significant decrease in fuel efficiency, potentially ranging from 10% to
25% or even more. Having your exhaust system repaired in a timely manner will ensure your vehicle will perform
at its top miles per gallon ability.
1 Leaking exhaust manifold: The most common symptoms of a leaking exhaust manifold are ticking noises,
a lit check engine light, odors in the exhaust, and clear damage on the manifold itself. The easiest and most
effective way to fix a leaking exhaust manifold is to replace it entirely.
2 Exhaust Pipe reaper
3 Muffler replacement

4 Catalytic converter service
5 Oxygen sensor replacement
6 Exhaust manifold repair
7 Hanger and Mount replacement

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CITS : Automotive - Mechanic Diesel - Lesson 25 - 28 CITS : Automotive - Mechanic Diesel - Lesson 25 - 28