ASE Ignition Systems 3

Question 1

What defines a coil-on-plug (COP) ignition system?

Accepted Answer

A dedicated ignition coil is mounted directly on each individual spark plug

Answer

One coil fires all cylinders through a single distributor

Answer

Two coils fire cylinder pairs through a common waste-spark arrangement

Answer

A single remote coil fires cylinders through long spark plug wires

Question 2

A weak or intermittent spark condition would most likely be caused by:

Accepted Answer

A failing ignition coil with a degraded secondary winding

Answer

Incorrect spark plug heat range installed

Answer

Excessive fuel pressure from a faulty regulator

Answer

A high idle speed condition

Question 3

What was the purpose of the ballast resistor in older ignition systems?

Accepted Answer

To limit primary coil current during normal operation to prevent coil overheating

Answer

To boost spark voltage during cold starting

Answer

To automatically advance timing at highway speeds

Answer

To filter radio frequency interference from the ignition

Question 4

On a secondary ignition oscilloscope pattern, what does an abnormally HIGH firing line indicate?

Accepted Answer

High resistance in the secondary circuit requiring more voltage to fire

Answer

Retarded ignition timing reducing combustion pressure

Answer

Low cylinder compression reducing the required firing voltage

Answer

Excessive fuel enrichment quenching the spark

Question 5

What is the minimum spark duration generally considered necessary for reliable combustion?

Accepted Answer

0.5 milliseconds

Answer

0.1 milliseconds

Answer

1.5 milliseconds

Answer

3.0 milliseconds

Question 6

Which type of distributor trigger sensor produces a clean digital square wave signal?

Accepted Answer

Hall-effect switch sensor

Answer

Magnetic inductive (variable reluctance) sensor

Answer

Piezoelectric knock sensor

Answer

Thermistor temperature sensor

Question 7

If a MAP sensor fails and reports falsely low vacuum (high load condition) to the PCM, what typically happens to ignition timing?

Accepted Answer

Timing retards to prevent knock under the falsely perceived high-load condition

Answer

Timing advances aggressively to compensate for perceived load

Answer

Timing remains fixed in open-loop fail-safe mode

Answer

Timing is controlled solely by crankshaft position with no load correction