Engine Performance 1 Final
Knock sensors require voltage input from the PCM to function properly.
All of the following statements are all correct EXCEPT ________.
Waste spark systems use a signal from the CMP to determine engine stroke.
All of the following statements are all correct EXCEPT ________.
2
Camshaft variation as displayed on a scan tool on an engine with a distributor-mounted CMP sensor should be plus or minus () ________ degrees.
an engine that is running rich
Carbon fouled spark plugs can be caused by:
Direction of the coil windings
Coil polarity is determined by the ________.
coil on plug
From which of the following ignition systems is it difficult for a technician to obtain a secondary ignition pattern?
The same plug always is fired the same way, whether it is straight or reverse polarity
How does a waste-spark ignition system fire the spark plugs?
Three
How many ignition coils should you expect to find on a V-6 engine using a waste spark system?
less than 4000V
How many volts should it take to fire a cylinder on the exhaust stroke?
Both Technicians
Ignition modules are being discussed. Technician A says they are used to turn the primary current on and off. Technician B says they are used to vary the dwell. Who is correct?
orange
In the diagram of the V-6 engine, which color represents cylinder #1?
higher firing voltage
Increased resistance in the secondary ignition circuit will cause:
3
A 6 cylinder engine with a waste spark system has how many coils?
none of the above
in the diagram of the V-6 engine, which color represents cylinder #4?
All of the above
A waste-spark-type ignition system fires ________.
it decreases
A worn ignition wire shorts to ground when wet. What happens to the firing voltage compared to normal operation?
Both Technicians
A 4 cylinder engine has the following firing voltages: 6 KV, 12 KV, 7 KV, and 7 KV. Technician A states that all plugs are firing within the normal range. Technician B states that there is too much variation between the highest and lowest values. Who is correct?
6
A 6 cylinder engine with a coil on plug ignition system has how many coils?
1
A 6 cylinder engine with a distributor ignition system has how many coils?
The coil secondary is open.
A coil is being checked, with the following results. What does the reading mean? OL
Start off flat then slope upward
A coil is being tested using current ramping. The waveform should ________.
Waste-spark
A compression-sensing ignition system uses a ________ type ignition.
Neither technician
A distributor ignition (DI) system has a Hall-Effect type pickup trigger. Technician A says that this type of pickup may be tested with an ohmmeter. Technician B says that this type of pickup produces an analog voltage signal. Who is right?
prevent pinging
A knock sensor (KS) circuit is used to:
Premature ignition coil failure
A loose spark plug is likely to cause:
Technician A
A no-start condition is being discussed on an engine equipped with a waste spark ignition system. Technician A says that a bad CKP (crankshaft position) sensor could be the cause. Technician B says that an open spark plug wire could be the cause. Who is right?
Fouled spark plugs Spark plug gap to narrow High resistance in the spark plug wire
A spark line that is too short could indicate?
A spark tester requires at least 25,000 volts to fire
A spark tester should be used to check for spark because ________.
3,000 V
A technician is measuring secondary ignition spark events with an oscilloscope. The firing line voltages vary between cylinders. What is the maximum acceptable variation?
Light tan or gray in color
A used spark plug in good condition has which of these characteristics:
A defective coil
A vehicle wil not start. A test light, placed on B+ and the negative side of the primary coil, flashes when the engine is cranked. Which of the following could be the problem?
Technician B only
A vehicle with a conventional distributor ignition (DI) system lacks power on acceleration, but it does not stumble or misfire. Technician A says that the ignition timing is too far advanced. Technician B says that a frozen centrifugal advance breaker plate is the most likely cause. Who is correct?
Technician B
A vehicle with an electronic ignition system (EI) has a loss of power with no engine misfiring. Technician A that says the base ignition timing may need to be adjusted. Technician B says that the exhaust system may be restricted. Who is right?
Both Technicians A and B
A vehicle with an ignition system triggered by a magnetic pulse generator will not start. Technician A says that the air gap should be checked using a go no-go stainless feeler gauge. Technician B says that the air gap is not adjustable. Who is correct?
distributor
All of the following are types of electronic ignition systems (EI) except:
Testing an ignition coil for resistance will always indicate its condition.
All of the following statements are correct EXCEPT ________
DIS
All these terms have been used to describe communication between the ignition module and PCM EXCEPT ________.
B only
An electronic distributor ignition (DI) system uses a Hall-Effect type pickup trigger. Technician A says you can test this type of pickup with an ohmmeter. Technician B says this type of pickup produces a digital voltage signal. Who is right?
5
An engine with a firing order of 142536 has a waste spark system. Which cylinder is the companion to cylinder 1?
Technician B only
An engine's initial timing is set at 6 degrees ATDC; the specification is 3 degrees BTDC. Technician A says the timing is overly advanced and must be retarded 9 degrees. Technician B says the timing is overly retarded and must be advanced. Who is correct?
Technician A only
An ignition coil is being inspected. Technician A says that there should be infinite resistance from the primary terminal and the coil housing. Technician B says that there should be infinite resistance across the two primary terminals. Who is correct?
Technician B only
An ohmmeter placed across the primary terminals of an ignition coil indicates 896 k ohms. Technician A says the coil windings are shorted. Technician B says the coil needs to be replaced. Who is correct?
True
An oscilloscope can be used to display the secondary ignition pattern.
WOT
Choose the condition that requires the ignition timing to be less advanced (retarded)
Lean air/fuel ratio
Choose the condition that will require ignition timing to be more advanced:
have pistons in the same position within the cylinder and are also going in the same direction
Companion cylinders are cylinders that:
Hall effect sensor Magnetic pulse generator sensor
Distributor ignition systems can be triggered by a ________.
0.25 volts AC
During cranking, most magnetic pulse generators should produce a minimum of ________.
Technician B only
Spark plugs are being discussed. Technician A says to remove the plugs when the engine is at normal operating temperature. Technician B says to use a torque wrench to tighten them. Who is correct?
engine speed Engine load
Spark timing is based on:
13.5 to 14.5 V
Supply voltage to the primary side of a EI coil should be:
Technician B
Technician A says that the primary coil has more windings. Technician B says that the secondary coil has more windings. Which technician is correct?
Both technicians
Technician A looks for engine speed (RPM) when cranking an engine that will not start. Technician B says that a problem in the primary circuit could make the tachometer not work. Which technician is correct?
Both A and B
Technician A says a pickup coil (pulse generator) can be tested with an ohmmeter. Technician B says ignition coils can be tested with an ohmmeter. Who is right?
Technician B
Technician A says a that an ohmmeter can be used to monitor the output signal of an optical sensor. Technician B says that optical sensors should be tested with an oscilloscope because of the sensor's speed. Which technician is correct?
Both Technicians
Technician A says most vehicles with electronic spark timing have to be placed into a "base timing mode" prior to checking initial timing. Technician B says the spark advance control of some distributor ignition system vehicles is built into the ignition module. Who is correct?
Both technicians
Technician A says that a defective crankshaft position sensor can cause a no-spark condition. Technician B says that a faulty ignition control module can cause a no-spark condition. Who is right?
Both technicians
Technician A says that a defective spark plug wire can cause an engine misfire. Technician B says that a defective spark plug can cause an engine misfire. Who is right?
Both Technician A and B
Technician A says that a hall effect crank shaft position sensor can be used to determine piston position. Technician B says that a magnetic crankshaft sensor can be used to determine piston position. Which technician is correct?
Both Technician A and B
Technician A says that a hall effect sensor creates a digital on and off signal that changes in frequency as the engine speed changes. Technician B says that an optical sensor uses LEDs and a phototransistor to signal the computer. Which technician is correct?
Both Technician A and B
Technician A says that a scope can be a useful tool to help diagnose ignition-related problems. Technician B says that a scope will show the spark line, which can be used to help diagnose problems with the ignition system. Which technician is correct?
Technician A
Technician A says that a thorough visual inspection should be performed on all ignition components when diagnosing an engine performance problem Technician B says that platinum spark plugs can be regapped after use in an engine. Who is right?
Both technicians
Technician A says that a two-wire COP system uses the PCM to trigger the coil. Technician B says that a three-wire COP system has an Integrated Circuit built into the coil assembly. Which technician is correct?
Both technicians
Technician A says that a waste spark ignition system fires two spark plugs at the same time. Technician B says that the waste spark ignition system uses ignition coils connected to companion cylinders. Which technician is correct?
Technician A
Technician A says that an oscilloscope can display the secondary ignition pattern in several displays making it easier to read or pinpoint a problem. Technician B says that an oscilloscope has only one display for the secondary ignition pattern to be displayed on. Which technician is correct?
Both Technician A and B
Technician A says that if there is one wire that is defective that it can cause two cylinders to be affected. Technician B says that a waste spark ignition system fires two spark plugs at the same time on paired cylinders with one being on compression stroke and the other on the exhaust stroke. Which technician is correct?
Technician B
Technician A says that ignition coil primary windings should have higher resistance than secondary windings. Technician B says that ignition coil secondary windings should have higher resistance than primary windings. Which technician is correct?
Neither Technician
Technician A says that ignition timing is retarded when RPM increases. Technician B states that ignition timing is advanced when load increases. Who is correct?
Technician B
Technician A says that in a waste spark ignition system both spark plugs fire straight polarity. Technician B says that one plug is fired with straight polarity and the other plug of the paired cylinder is always fired in reverse polarity. Which technician is correct?
Both technicians
Technician A says that in bypass mode, the ignition system is timed by the ignition module. Technician B says that in bypass mode, the ignition system does not use the PCM to time spark plug firing. Which technician is correct?
Technician A
Technician A says that in the inside of the ignition coil there are primary and secondary coil windings. Technician B says that the primary coil windings are made of fine wire wrapped around a laminated soft iron core. Which technician is correct?
Technician B
Technician A says that indexing the distributor is the same as setting ignition timing. Technician B says that a distributor that is not phased correctly can cause a misfire and rough idle. Who is right?
Both Technician A and B
Technician A says that it requires a minimum of 25,000 volts to jump a gap of ¾ of an inch. Technician B says that a standard spark plug removed from the cylinder used to check for spark only requires 3,000 volts or less to create a spark so the use of a spark tester is required otherwise you may overlook a bad coil. Which technician is correct?
Technician B
Technician A says that the ignition timing cannot be adjusted on distributor ignition systems. Technician B says that most waste spark systems use a crankshaft position sensor. Which technician is correct?
Technician B
Technician A says that the primary and secondary ignition systems are never connected. Technician B says that the primary and secondary windings are connected in some ignition coils. Which technician is correct?
Both Technician A and B
Technician A says that the primary windings in a coil are used to create a strong magnetic field that, when collapsed, induces a high voltage into the secondary windings. Technician B says that when the circuit is opened the magnetic field collapses. Which technician is correct?
Both Technician A and B
Technician A says that when doing a visual inspection to look for any signs of a spark plug wire that has been damaged. Technician B says to look for a coil that is leaking and to check for signs of carbon tracking on the distributor cap and wires. Which technician is correct?
Both Technician A and B
Technician A says that you can use a spray bottle to spray water on wires and plugs to help find an intermittent fault. Technician B says to listen with the engine running for any audible snapping noises that could indicate a defective wire or cap. Which technician is correct?
Technician A
Technician A says to check for spark at the spark plug or secondary circuit by using a spark tester. Technician B says to check for spark by removing the ignition wire and looking for a spark. Which technician is correct?
Neither Technician A nor B
Technician A says to test spark plug wires by removing them when the vehicle is running and looking for a spark. Technician B says to attach a test light to the end of the spark plug wire and see if it lights up. If it does then the wire is good. Which technician is correct?
Both Technicians
Technician A states that most electronic ignition systems have no method for the technician to set ignition timing. Technician B states that the advance curves are determined by the PCM. Who is correct?
Powertrain Control Module Crankshaft sensor Magnetic Pulse Generator (pickup coil)
Technicians are discussing ignition systems in general. If the ignition module has control over the firing of the coil(s) of an EI system, which component(s) could trigger (control) the ignition module?
the amount of time that the primary current is turned on
The dwell section of a primary scope pattern represents:
Ignition module
The ignition system pickup coil or trigger is usually electrically connected to the ________.
Technician B only
The non-electronic spark advance of an engine is not increasing as engine rpm increases. Technician A says the vacuum advance unit may have a leaking diaphragm. Technician B says the centrifugal advance weights may be stuck. Who is correct?
Spark plug wires
The primary (low-voltage) ignition system must be working correctly before any spark occurs from a coil. Which component is NOT in the primary ignition circuit?
Signals the electronic control unit (module)
The pulse generator ________.
.8 msec
The spark burn time should be at least:
Thread chaser
The spark plug threads in the cylinder head should be cleaned using a(an) ________ before installing new plugs.
decrease plug life
Too high of a heat range spark plug will:
Neither technician
Two technicians are discussing a no-start condition. During cranking, a magnet held over the coil moves and the engine backfires at times. Technician A says that a bad pickup coil or CKP sensor is the most likely cause. Technician B says that an open coil primary is the most likely cause. Which technician is correct?
Both technicians
Two technicians are discussing distributor ignition. Technician A says that the magnetic pulse generator (pickup coil) or optical sensor in the distributor is used to pulse the ignition module (igniter). Technician B says that some distributor ignition systems use a Hall effect sensor sensor. Which technician is correct?
B only
Two technicians are measuring secondary ignition events with an oscilloscope. Technician A says that a worn electrode will cause the firing voltage to decrease. Technician B says that the burn line will be shortened if the firing line is lengthened. Who is correct?
0.5 to 3
Typical primary coil resistance specifications usually range from ________ ohms.
6,000-30,000
Typical secondary coil resistance specifications usually range from ________ ohms
Both technicians
Waste spark ignition is being discussed. Technician A says it requires more voltage to fire the compression cylinder than the companion cylinder. Technician B says waste spark systems that use compression sensing electronics do not require a camshaft sensor for engine position. Which technician is correct?
plug that is firing while the piston is on the exhaust stroke
Waste spark refers to the:
Electromagnetic induction
What is the principle used to create high voltage from low voltage?
Both A and B
When diagnosing a no-start condition on a vehicle with no spark, Technician A says that the ignition module should be tested for a digital switching signal. Technician B says the Hall effect CMP sensor should be tested for a digital switching signal. Who is right?