ch 61

Many oscilloscopes have the ability to stack each spark plug's ignition pattern vertically, which is called ________. Parade pattern Raster Both A and B Neither A nor B

Raster

As engine rpm increases, the ignition timing must:

advance

Tech A says that as engine RPM increases, spark timing generally increases. Tech B says that as engine load increases, spark timing generally decreases. Who is correct?

both

Tech A says that as engine rpm increases, spark timing generally increases. Tech B says that as engine load increases, spark timing generally decreases. Who is correct?

both

Tech A says that some spark plugs are made with iridium and platinum and can last 100,000 miles. Tech B says that some plugs will need to be replaced at 30,000 miles. Who is correct?

both

Most vehicles today use the ______ type of ignition system. Coil-on-plug Waste spark Breakerless Distributor

coil on plug

Which of the following systems has the fewest parts, which reduces failures and maintenance the most? Waste spark ignition system Coil-on-plug ignition system Contact breaker point ignition system Distributor-type electronic ignition system

coil on plug

In electronically triggered ignition systems, the spark timing is engineered into the design of the engine and is not adjustable. Which component measures engine speed? Throttle position sensor Manifold absolute pressure sensor Crankshaft position sensor Mass airflow sensor

crankshaft postion

On an engine with a separate coil for each spark plug, performing a power balance test may involve: disconnecting each individual coil one at a time to disable one cylinder at a time. disconnecting the fuel injector wire connections at all injectors before starting the engine. pulling the IGN fuse so the engine won't start. pulling the PCM fuse so the engine won't start.

disconnecting each individual coil one at a time to disable one cylinder at a time

On an engine with a separate fuel injector for each cylinder, cylinder power balance tests may involve: disconnecting the primary electrical connector to each individual coil first. disconnecting the fuel injector wire connection at each individual injector one at a time. pulling the fuel pump relay or fuse. pulling the ECM fuse to make sure the engine doesn't start.

disconnecting the fuel injector wire connection at each individual injector one at a time.

All of the following components are common to all ignition systems except: spark plugs. the ignition coil. a device for triggering the ignition coil. a distributor.

distributor

Although there are several types of ignition systems, the common components include the spark plugs, the ______, and a device for triggering the ignition coil. Cylinder Tachometer Ignition coil Electrodes

ignition coil

Which of the following does the ignition system use to convert relatively low-voltage and high-current flow into very high-voltage and very low-current flow? induction coil Ignition switch Ignition module Spark plugs

induction coil

When testing intake manifold vacuum, a low steady reading at idle is likely to be caused by: a burned exhaust valve. a partially restricted exhaust. late ignition timing or valve timing. None of the answers listed

late ignition timing or valve timing

The ignition system must also be able to advance or retard the timing of the spark, based on engine conditions such as ________, speed, and driver input.

load

When testing intake manifold vacuum, the gauge needle oscillates back and forth rapidly, which generally indicates: a partially restricted exhaust. a mechanical condition such as a burned or bent valve. late ignition or valve timing. None of the answers listed

mechanical condition such as a burned or bent valve

Which of the following ignition switch positions unlocks the steering column but does not enable any electrical systems or disable the engine immobilizer or theft-deterrent system? Lock Off Accessory On

off

Finding breakdowns in coil insulation requires the coil to be activated and the available voltage to be measured on a(n) ________ and compared to specifications. Multimeter Oscilloscope Temperature gauge None of the above

oscilloscope

The pattern in which a lab scope shows all the cylinders firing in sequence is called the: parade pattern. raster pattern. spark line. firing line.

parade pattern

The amount of voltage needed to initially get the spark to jump the spark plug gap is called the: available voltage. required voltage. induced voltage. None of the above

required voltage

Which of these usually increases primarily because of the growing gap of the spark plug as it wears over time? Required voltage Available voltage Reserve voltage Primary voltage

required voltage

Tech A says that a defective crankshaft or camshaft position sensor can prevent an engine from starting. Tech B says that if a diagnostic trouble code (DTC) indicates a problem with the crankshaft or camshaft position sensor, you will always have to replace the sensor. Who is correct?

tech a

Tech A says that contact breaker points are a mechanical switch that opens and closes once for every ignition spark that is created. Tech B says that contact breaker points send high voltage directly from the points to the spark plugs. Who is correct?

tech a

Tech A says that on a secondary ignition pattern, the firing line shows how much voltage it takes to jump the spark plug gap. Tech B says that the spark line on a secondary pattern tells the length of the spark plug reach. Who is correct?

tech a

Tech A says that a Hall-effect switch uses light to turn a circuit on and off. Tech B says that waste spark systems don't need distributors. Who is correct?

tech b

Tech A says that as engines gain miles, the spark plug gap increases, which raises the ignition system's available voltage. Tech B says that misfire occurs when required voltage is higher than available voltage. Who is correct?

tech b

Tech A says that coil-on-plug ignition systems use one coil to fire two cylinders. Tech B says that you should twist spark plug boots before removing them. Who is correct?

tech b

Tech A says that the ignition system will maintain spark at the spark plug for approximately 23 degrees of crankshaft rotation. Tech B says that the duration of spark in the spark plug only lasts 2 to 3 degrees of crankshaft rotation. Who is correct?

tech b

Tech A says that the positive side of the coil primary circuit is typically switched by the ignition module. Tech B says that on two-wire COP coils, the coil is switched by an external ignition module or the PCM. Who is correct?

tech b

Tech A states that when the driver turns the key to the Start position, an electrical connection is made between the vehicle battery and the secondary winding of the ignition coil. Tech B states that as the engine is cranked, a switching circuit turns the primary ignition coil circuit on and off. Who is correct?

tech b

If there is a slight drag between the gapping tool gauge and the spark plug electrodes as the gauge is installed and removed, it means: the gap of the spark plug is correct. the gap of the spark plug is too high. the gap of the spark plug is too low. the spark plug was not pre-gapped.

the gap of the spark plug is correct

A good wire will have a maximum of 3,000 to 7,000 ohms of resistance per foot of wire.

true

As the high voltage pushes current across the spark plug electrodes, the air fuel mixture is ignited, causing very high pressure, which in turn pushes the piston down on the power stroke.

true

Some manufacturers recommend that the spark plugs only be replaced on a cold engine to avoid damaging the threads in the cylinder head.

true \

The type of ignition system in which two cylinders share one coil is called a: distributor ignition system. waste spark ignition system. coil-on plug ignition system. None of the above

waste spark ignition system

How even should the cranking compression be between the lowest and highest cylinder readings on an engine without mechanical problems? Within 0% to 5% Within 10% to 15% Within 20% to 25% Within 30% to 35%

within 10% to 15%