ASEP 108 - Chapter 9 Classroom Manual

A waste spark ignition system equipped vehicle has a no-spark condition. Technician A says the crankshaft position sensor may be defective. Technician B says the ignition module may be defective. Who is correct?

Both A and B

In an ion sensing ignition system, information about the combustion chamber is determined by the:

Spark plug

The ignition coil is both a primary and secondary ignition component.

TRUE

Spark plugs are being discussed: Technician A says iridium spark plugs should not have the gap checked by the technician. Technician B says platinum spark plugs should not have the electrode filed. Who is correct?"

Both Technician A and B are correct

Technician A says the primary ignition coil can be tested with an Ohmmeter. Technician B says the secondary ignition coil can be tested with an oscilloscope. Who is correct?

Both A and B

Technician A says the magnetic pick-up may be tested using a voltmeter to measure the AC voltage during cranking. Technician B says the Hall-effect sensor produces a square wave pattern on an oscilloscope. Who is correct?

Both A and B

A defective crankshaft position sensor is a common cause of a no-start condition.

TRUE

On most electronic ignition systems base timing needs to checked and adjusted whenever the system is serviced.

FALSE

A shorted secondary coil winding provides an ohmmeter reading above the specified resistance.

FALSE

The ignition switch, primary coil winding, and module are all components of:

The primary ignition circuit.

Technician A says one component of the secondary ignition circuit is the coil. Technician B says the coil is a component in the primary ignition circuit. Who is correct?

Both A and B

A Hall-effect switch is being analyzed on a lab scope. The high part of the signal measures 5.0 volts. Ideally, what should the low part of the signal read?

0.0 volts

While discussing the diagnosis of an EI system, Technician A says the primary coil normally has between 5,000 and 20,000 ohms of resistance. Technician B says the coil secondary normally has less than 2 ohms of resistance. Who is correct?

Neither A nor B

Technician A says that if the spark plug wire terminal ends are not clean and tight, the terminals should be cleaned and recrimped. Technician B says the spark plug wires need to be replaced. Who is correct?

Technician B

The time during which current flows through the primary coil winding is called:

Dwell

The parade pattern on an oscilloscope displays cylinder patterns from right to left.

FALSE

Technician A says the ignition coil is actually where the primary and secondary circuits meet. Technician B says bypass voltage is sent from the ECM to tell the module to switch to computer based timing. Who is correct?"

Both A and B

If dwell time is to short, the coil and module can overheat.

FALSE

Waste spark systems deliver spark to two cylinders at once.

TRUE

Technician A says the crankshaft position sensor can be a Hall-effect switch. Technician B says the crankshaft position sensor can be a magnetic pulse generator. Who is correct?

Both A and B

Base timing is the initial timing specified by the:

Manufacturer

Ignition cables are usually made of solid wire which acts as a resistor in the secondary circuit.

FALSE

An oscilloscope test shows firing lines the same, but abnormally high. This is the result of:

A lean air/fuel mixture.

The raster pattern on an oscilloscope displays cylinder patterns:

Stacked one above the other

Technician A says if the firing voltage is higher than normal the burn time will decrease. Technician B says if the firing voltage is lower than normal the burn time will decrease. Who is correct?

Technician A

The firing voltages of a four cylinder engine are as follows: #1: 8kV; #2: 27kV; #3: 4kV; and #4: 9kV. Which of the following is true?

Cylinder #2 may have an open plug wire.

The heat range of a spark plug refers to its ability to retain heat.

FALSE

Base or initial timing is timing with computer advance added.

FALSE

Technician A says the ignition timing must retard as RPM increases. Technician B says ignition timing is retarded under maximum load. Who is correct?

Technician B

All of the following situations may call for timing advance except:

Heavy engine load

Ford's EI systems are being discussed: Technician A says the CKP sensor is a variable reluctance sensor. Technician B says the system uses a separate ignition module. Who is correct?

Technician A

While discussing the diagnosis of an EI system in which the crankshaft and camshaft sensor tests are satisfactory but a spark tester connected from the spark plug wires to ground does not fire, Technician A says the coil assembly may be defective. Technician B says the voltage supply wire to the coil assembly maybe open. Who is correct?

Both A and B

Compression sense ignition allows for the elimination of the:

Camshaft sensor

Technician A says as engine speed slows, the timing should be retarded or have less advance. Technician B says typically, the more load on an engine, the less spark advance is needed. Who is correct?

Both A and B

While discussing the testing of a Hall-effect switch, Technician A says that the Hall-effect switch should read zero volts with the feeler gauge inserted between the hall layer and the magnet with battery voltage applied. Technician B says that the Hall-effect switch can only be tested with a scan tool. Who is correct?"

Technician A