Discuss three sources of hydrocarbons (HC).
What will be an ideal response?
- Blowby gases are those that leak past the piston rings. Crankcase ventilation systems remove these vapors from the crankcase.
- After each four-stroke cycle is completed, raw gasoline remains on all areas of the combustion chamber. This happens because the surface area of the combustion chamber is cold. Burning fuel is quenched on cylinder surfaces; this is called the skin effect. HC emissions are higher when a combustion chamber has more surface area.
- Raw gas accumulates in the exhaust system when combustion is incomplete because the air-fuel mixture is too rich.
- When a cylinder does not produce sufficient compression to burn the mixture, unburned HCs will exit the cylinder.
- An ignition system that does not provide adequate spark will increase HC emissions.
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A vehicle being inspected under an OBD-II testing program and the MIL is ON. What will be the results of the inspection?
A) The vehicle will fail the test.
B) The vehicle will receive an 80% pass rate.
C) The vehicle will pass the test.
D) None of these
How is the condensate from the evaporator disposed of in a basement installation?
A) Condensate does not form on the coil when it is installed in a cool location. B) By using a condensate pump C) The condensate drain can be plugged to prevent water from leaving, eliminating the need for a drain. D) The air pressure in the system pushes the condensate up no more than 3 feet above the drain pan.
Each memory location must have a unique
A) contents. B) address. C) timing. D) byte.
Two technicians are discussing a Hemi engine. Technician A says that a Hemi is an engine with a
hemi-spherical shaped combustion chamber. Technician B says that all Hemi engines are cam-in-block designs. Which technician is correct? A) Technician A only B) Technician B only C) Both technicians A and B D) Neither technician A nor B