7290-157 L6 Emissions

Which component changes HC & CO into H₂O & CO₂ ?

• Reduction Converter

• Oxidisation Converter

• DPF

• Piezoelectric Converter

If there is an air leak at manifold what would symptoms be?

• Improved fuel consumption

• lower HC

• High HC

• Car not starting

At what temperature do Oxides of Nitrogen become high?

• 1400°C

• 1400°F

• 850°C

• 650°F

What are the three precious metals used in a Catalytic converter?

• Platinum, Gold, Argon

• Gold, Frankincense, Myrrh

• Platinum, Palladium, Rhodium

• Rhodium, Silver, Argent

What is the stoichiometric ratio?

• 147:1

• 14.1:7

• 1:14.7

• 14.7:1

If a misfire occurs what is most likely to happen?

• Catalyst runs excessively hot.

• Catalyst runs excessively cold

• Petrol will wash Honeycomb of precious metal

• The catalyst will catch fire

What reading is expected from the pre-cat sensor?

• A constant 12v

• Fluctuation from 0.2 - 0.8v

• Constant 5v

• Same as post cat sensor

How does EGR improve emissions?

• It pre warms catalytic converter

• It increases combustion temperature

• It reduces combustion temperature

• It dumps exhaust gases in to air intake

When testing EGR, the actuator tests do not work, what is a likely fault?

• ECU damaged

• OBD reader not connected

• Overvoltage in vacuum circuit

• Split vacuum pipe

How does a emission tester check Diesel emissions?

• It measures four gases from exhaust

• It uses a light in a box

• It sends smoke through EGR

• Diesels do not have emissions