Evaporative emission control system.
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Transcript of Evaporative emission control system.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
OBJECTIVESAfter studying Chapter 26, the reader will be able
to:
.1Prepare for the ASE Engine Performance (A8) certification test content area “D” (Emission
Control Systems).
.2Describe the purpose and function of the evaporative emission control system.
.3Discuss how the evaporative emission control system is tested under OBD-II regulations.
.4Explain methods for diagnosing and testing faults in the evaporative emission control
system.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
NEED FOR EVAPORATIVE EMISSION CONTROL
The purpose of the evaporative (EVAP) emission control system is to trap and hold gasoline vapors .
The charcoal canister is part of an entire system of hoses and valves .
Before the early 1970s, most gasoline fumes were simply vented to the atmosphere.
The purpose of the EVAP system is to trap gasoline vapors—volatile organic compounds, or VOCs—
that would otherwise escape into the atmosphere .These vapors are instead routed into a charcoal
canister, from where they go to the intake airflow so they are burned in the engine.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
NEED FOR EVAPORATIVE EMISSION CONTROLCommon Components
Most EVAP fuel tank filler caps have pressure-
vacuum relief built into them .
When pressure or vacuum exceeds a
calibrated value, the valve opens .
Once the pressure or vacuum has been
relieved, the valve closes.
FIGURE 26-1 A typical bayonet-type gas cap.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
VAPOR CANISTER STORAGEThe canister is located
under the hood or underneath the vehicle,
and is filled with activated charcoal
granules that can hold up to one-third of their
own weight in fuel vapors .
A vent line connects the canister to the fuel tank.
FIGURE 26-2 Charcoal canister as mounted under the hood (Jeep). Not all charcoal canisters are this accessible; in fact, most are hidden under the hood or in other locations on the vehicle.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
VAPOR CANISTER STORAGE
FIGURE 26-3 The evaporative emission control system includes all of the lines, hoses, and valves, plus the charcoal canister.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
VAPOR PURGINGDuring engine operation, stored vapors are
drawn from the canister into the engine through a hose connected to the throttle body
or the air cleaner .This “purging” process mixes HC vapors from
the canister with the existing air-fuel charge.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
VAPOR PURGINGComputer-Controlled Purge
Canister purging on engines with electronic fuel management systems is regulated by the
powertrain control module (PCM).Control of this function is particularly
important because the additional fuel vapors sent through the purge line can upset the air–fuel ratio provided by a fuel-injection system .
Since air–fuel ratio adjustments are made many times per second, it is critical that vapor
purging is controlled just as precisely.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
VAPOR PURGINGComputer-Controlled Purge
FIGURE 26-4 A typical evaporative emission control system. Note that when the computer turns on the canister purge solenoid valve, manifold vacuum draws any stored vapors from the canister into the engine. Manifold vacuum also is applied to the pressure control valve. When this valve opens, fumes from the fuel tank are drawn into the charcoal canister and eventually into the engine. When the solenoid valve is turned off (or the engine stops and there is no manifold vacuum), the pressure control valve is spring-loaded shut to keep vapors inside the fuel tank from escaping to the atmosphere.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
EVAPORATIVE SYSTEM PRESSUREPressures can build inside the fuel system and
are usually measured in units of inches of water, abbreviated in. H2O. (28 inches of
water equals one PSI) .Pressure buildup is a function of:
Fuel evaporation rates (volatility)Gas tank size (fuel surface area and volume)Fuel level (liquid versus vapor)Fuel slosh (driving conditions)Temperature (ambient, in-tank, close to the tank)Returned fuel from the rail
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
NONENHANCED EVAPORATIVE CONTROL SYSTEMS
Nonenhanced evaporative systems use
either a canister purge solenoid or a vapor
management valve to control purge vapor.
FIGURE 26-5 A typical OBD-II EVAP system which uses fuel tank pressure
and purge flow sensors to detect leaks and measure purge flow. The purge
flow sensor is similar to a mass air flow sensor and measures the amount of
flow into the engine.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
ENHANCED EVAPORATIVE CONTROL SYSTEM
All vehicles built after 1995 have enhanced evaporative systems that have the ability to
detect purge flow and system leakage .If either of these two functions fails, the
system is required to set a diagnostic trouble code and turn on the MIL light to warn the
driver of the failure.Vent ValvePurge Valve
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
ENHANCED EVAPORATIVE CONTROL SYSTEM
FIGURE 26-6 The vapor management valve (VMV) and the canister purge valve (CPV) are both PCM controlled and check for proper flow through the evaporative control system. The fuel tank pressure (FTP) sensor monitors vapor pressure inside the fuel tank.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
ONBOARD REFUELING VAPOR RECOVERY
The primary feature of most ORVR systems is the restricted tank filler tube, which is about 1
inch (25 mm) in diameter.This reduced filler tube creates an aspiration
effect, which tends to draw outside air into the filler tube .
During refueling, the fuel tank is vented to the charcoal canister, which captures the gas
fumes: with air flowing into the filler tube, no vapors can escape to the atmosphere.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
STATE INSPECTION EVAP TESTSIn some states, a
periodic inspection and test of the fuel system
are mandated along with a dynamometer test .
The emissions inspection includes tests on the
vehicle before and during the dynamometer
test.
FIGURE 26-7 A gas cap being testing by an inspector at an inspection station.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
DIAGNOSING THE EVAP SYSTEMBefore vehicle emissions testing began in
many parts of the country, little service work was done on the evaporative emission
system .Common engine-performance problems that
can be caused by a fault in this system include:
Poor fuel economyPoor performance
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
DIAGNOSING THE EVAP SYSTEM
FIGURE 26-8 A typical purge flow tester connected in series between the intake manifold (or control solenoid) and the charcoal canister. Most working systems should be capable of flowing at least 1 L/min. Some vehicles must be test driven because their computers only purge after a certain road speed has been achieved.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
LOCATING LEAKS IN THE SYSTEMLeaks in the evaporative emission control system will
cause the malfunction check gas cap indication light to come on in some vehicles.
FIGURE 26-9 Some vehicles will display a message if an evaporative control system leak is detected that could be the result of a loose gas cap.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
LOCATING LEAKS IN THE SYSTEMThere are two methods that can be used to
check for leaks in the evaporative system.Smoke machine testing .Nitrogen gas pressurization.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
LOCATING LEAKS IN THE SYSTEM
FIGURE 26-10 (a) A typical EVAP diagnostic tester. (b) A smoke test shows a leaking gas cap.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
LOCATING LEAKS IN THE SYSTEM
FIGURE 26-11 An emission tester that uses nitrogen to pressurize the fuel system.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
EVAPORATIVE SYSTEM MONITORThe EVAP system
monitor tests for purge volume and leaks .
Most applications purge the charcoal canister by venting the vapors into
the intake manifold during cruise .
To do this, the PCM typically opens a
solenoid-operated purge valve installed in the
purge line leading to the intake manifold.
FIGURE 26-12 Typical evaporative system showing the valves and the normal position.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
EVAPORATIVE SYSTEM MONITOREngine Off Natural Vacuum
System integrity (leakage) can also be checked after the engine is shut off .
The premise is that a warm evaporative system will cool down after the engine is shut off and the
vehicle is stable.A slight vacuum will be created in the gas
tank during this cooldown period .If a specific level of vacuum is reached and
maintained, the system is said to have integrity (no leakage).
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERAL MOTORS ENHANCED EVAP
The PCM will run the EVAP monitor when the following enable criteria are met .
Typical enable criteria include:Cold startBARO greater than 70 kPa (20.7 in. Hg or 10.2 PSI)IAT between 39°F and 86°F at engine start-upECT between 39°F and 86°F at engine start-upECT and IAT within 39°F of each other at engine
start-upFuel level within 15% to 85%TP sensor between 9% and 35%
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERAL MOTORS ENHANCED EVAPRunning the EVAP Monitor
There are four tests which are performed during a typical GM EVAP monitor .
A DTC is assigned to each test.Weak Vacuum Test (P0440—large leak) .Small Leak Test (P0442—small leak) .Excess Vacuum Test (P0446) .Purge Solenoid Leak Test (P1442).
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
ALWAYS TIGHTEN “THREE CLICKS”
FIGURE 26-13 Some newer Fords use a fuel system that does not use a cap. Carefully check the opening for dirt or debris if an evaporative system DTC is set.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
FORD ENHANCED EVAPThe PCM will run the EVAP monitor when the
following enable criteria are met.Cold startInlet air temperature between 40°F and 100°F6 -to 8-hour engine soak timer must expire
A PCM reset (without turning the ignition off) will bypass the 6- to 8-hour engine soak timer.
Altitude less than 8,000 feetFuel level within 15% to 85% (40% min for 0.020
in. leak)40 to 65 mph steady cruise30-minute time limit for the monitor to run
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
FORD ENHANCED EVAPTypical Ford Strategy
Phase 0—Initial Vacuum Pulldown.Phase 1—Vacuum Stabilization.Phase 2—Vacuum Hold and Decay.Phase 3—Vacuum Release.Phase 4—Vapor Generation.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEEP THE FUEL TANK PROPERLY FILLED
FIGURE 26-14 The fuel level must be above 15% and below 85% before the EVAP monitor will run on most vehicles.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
LEAK DETECTION PUMP SYSTEMMany Chrysler and some
other brands of vehicles use a leak detection
pump (LDP) as part of the evaporative control
system diagnosis equipment.
FIGURE 26-15 A leak detection pump (LDP) used on some Chrysler vehicles to pressurize (slightly) the fuel system
to check for leaks.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
LEAK DETECTION PUMP SYSTEMPump Period
The time between LDP solenoid off and LDP switch close is called the pump period .
This time period is inversely proportional to the size of the leak .
The shorter the pump period, the larger the leak .
The longer the pump period, the smaller the leak.
EVAP large leak (>0.080): less than 0.9 secondsEVAP medium leak (0.040 to 0.080): 0.9 to 1.2
secondsEVAP small leak (0.020 to 0.040): 1.2 to 6 seconds
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
EVAP SYSTEM-RELATED DIAGNOSTIC TROUBLE CODES (DTCs)
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
SUMMARY.1The purpose of the evaporative emission
(EVAP) control system is to reduce the release of volatile organic compounds (VOC)
into the atmosphere.
.2A carbon (charcoal) canister is used to trap and hold gasoline vapors until they can be
purged and run into the engine to be burned.
.3Pressures inside the EVAP system are low and are measured in inches of water (1 PSI
= 28 in. H2O).
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
SUMMARY.4A typical EVAP system uses a canister purge
valve, which is normally closed, and a canister vent valve, which is normally open.
.5OBD-II regulation requires that the evaporative emission control system be checked for leakage
and proper purge flow rates..6External leaks can best be located by
pressurizing the fuel system with low-pressure smoke.
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
REVIEW QUESTIONS.1What components are used in a typical
evaporative emission control system?.2How does the computer control the purging
of the vapor canister?.3What is the difference between an enhanced
and nonenhanced evaporative control system?
.4How is a flow gauge used to diagnose the evaporative emission control system?
.5What are the parameters (enable criteria) that must be met for the evaporative system
monitor to run?
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ.1What is the substance used in a vapor
canister to absorb volatile organic compounds?
(aDesiccant(bOrganic absorber(cPleated paper(dCarbon
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ.1What is the substance used in a vapor
canister to absorb volatile organic compounds?
(aDesiccant(bOrganic absorber(cPleated paper(dCarbon
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ2.Which valve(s) is (are) normally closed?
(aCanister purge valve(bCanister vent valve(cBoth canister purge and canister vent valve(dNeither canister purge nor canister vent valve
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ2.Which valve(s) is (are) normally closed?
(aCanister purge valve(bCanister vent valve(cBoth canister purge and canister vent valve(dNeither canister purge nor canister vent valve
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ3.All of the following can increase the pressure
in the evaporative emission control system except _____
(aFuel temperature(bReturned fuel from the fuel-injection system(cInlet fuel to the fuel pump(dRVP of the fuel
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ3.All of the following can increase the pressure
in the evaporative emission control system except _____
(aFuel temperature(bReturned fuel from the fuel-injection system(cInlet fuel to the fuel pump(dRVP of the fuel
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ4.Evaporative emission control systems operate
on low pressure measured in inches of water (in. H2O). One PSI is equal to how many
inches of water?(a1
(b10
(c18
(d28
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ4.Evaporative emission control systems operate
on low pressure measured in inches of water (in. H2O). One PSI is equal to how many
inches of water?(a1
(b10
(c18
)d28
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ5.Inadequate purge flow rate will trigger which
DTC?(aP0440(bP0441(cP0300(dP0301
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ5.Inadequate purge flow rate will trigger which
DTC?(aP0440(bP0441(cP0300(dP0301
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ6.Two technicians are discussing a P0442 DTC.
Technician A says that it can be caused by a leaking EVAP line. Technician B says that a
leaking gas cap can cause a failure of the EVAP test. Which technician is correct?
(aTechnician A only(bTechnician B only(cBoth Technicians A and B(dNeither Technician A nor B
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ6.Two technicians are discussing a P0442 DTC.
Technician A says that it can be caused by a leaking EVAP line. Technician B says that a
leaking gas cap can cause a failure of the EVAP test. Which technician is correct?
(aTechnician A only(bTechnician B only(cBoth Technicians A and B(dNeither Technician A nor B
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ7.A flow gauge is being used to check for proper
canister pump flow rate. What is the specification used by most emission test
sites?(a10 liters per minute(b5 liters per minute(c1 liter in 4 minutes(d0.5 liter per hour
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ7.A flow gauge is being used to check for proper
canister pump flow rate. What is the specification used by most emission test
sites?(a10 liters per minute(b5 liters per minute)c1 liter in 4 minutes(d0.5 liter per hour
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ8.Before an evaporative emission monitor will
run, the fuel level must be where?(aAt least 75% full(bOver 25%(cBetween 15% and 85%(dThe level of the fuel in the tank is not needed to
run the monitor test
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ8.Before an evaporative emission monitor will
run, the fuel level must be where?(aAt least 75% full(bOver 25%(cBetween 15% and 85%(dThe level of the fuel in the tank is not needed to
run the monitor test
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ9.Technician A says that low pressure smoke
installed in the fuel system can be used to check for leaks. Technician B says that
nitrogen under low pressure can be installed in the fuel system to check for leaks. Which
technician is correct?(aTechnician A only(bTechnician B only(cBoth Technicians A and B(dNeither Technician A nor B
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ9.Technician A says that low pressure smoke
installed in the fuel system can be used to check for leaks. Technician B says that
nitrogen under low pressure can be installed in the fuel system to check for leaks. Which
technician is correct?(aTechnician A only(bTechnician B only(cBoth Technicians A and B(dNeither Technician A nor B
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ10.A large leak is detected by the evaporative
emission control system monitor that could be caused by a loose gas cap. Which DTC
will likely be set?(aP0440(bP0442(cP0446(dEither P0440 or P0442
Automotive Fuel and Emissions Control Systems, 2/eBy James D. Halderman and Jim Linder
© 2009 Pearson Higher Education, Inc.Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ10.A large leak is detected by the evaporative
emission control system monitor that could be caused by a loose gas cap. Which DTC
will likely be set?(aP0440(bP0442(cP0446(dEither P0440 or P0442