ch 22 & 23 engines

A good engine should produce how much compression during a running (dynamic) compression test at idle?

60-90 PSI

Which of these smoke types indicates oil being burned in the combustion chamber?

Blue

A smoothly operating engine depends on ________.

Equal compression between cylinders

A technician is preparing to do an oil change on a hybrid vehicle. What special precaution needs to be taken BEFORE performing this service?

Make sure the ignition is "OFF" and the key is removed from the ignition switch.

Hybrid electric vehicles usually require special engine oil of what viscosity?

SAE 0W-20

The low oil pressure warning light usually comes on ________.

When oil pressure drops dangerously low (4 to 7 psi)

Antifreeze mixed with engine oil can cause ________. Oil becomes thinner (decrease viscosity) Oil becomes thicker (increase viscosity) Oil congeals (become solid)

a & c

A thermostat can fail in which way? Stuck partially open Stuck open Stuck closed

all

When replacing a timing belt, many experts and vehicle manufacturers recommend that what other part(s) should be replaced? Tensioner assembly Camshaft oil seal(s) Water pump

all

Technician A says that a leaking head gasket can be tested for by using a chemical tester. Technician B says that a leaking head gasket can be found using an exhaust gas analyzer. Who is correct?

both techs

An intake manifold gasket has been replaced due to a vacuum leak. Which of the following steps uses a scan tool to complete the job?

idle relearn

Most mechanical engine problems are caused by which of these?

overheating

A defective thermostat can cause the powertrain control module (PCM) to set what diagnostic trouble code (DTC)?

p0128

A vehicle has set DTC P0172, indicating a lean exhaust and a vacuum leak is suspected. This can be diagnosed by introducing ________ around the intake manifold gasket.

propane

Technician A says that the first step in diagnosing engine condition is to perform a thorough visual inspection. Technician B says that oil leaks can be found by measuring straight up from where the oil drips on the floor. Which technician is correct?

tech a

Technician A says that a compression test can be used to test the condition of connecting rods. Technician B says that a cylinder leakage test fills the cylinder with compressed air, and the gauge indicates the percentage of leakage. Which technician is correct?

tech b

Technician A uses a steel gasket scraper on aluminum engine parts. Technician B uses a plastic or wood scraper on aluminum engine parts. Which technician is correct?

tech b

Coolant leaking from an intake manifold can evaporate fast enough to leave no trace of a leak.

true

Which of the following is the LEAST LIKELY to cause an engine noise?

vacuum leak

On some engines equipped with a timing belt, the belt also may drive the ________.

water pump