check engine FORD MUSTANG 2003 Workshop Manual

DIAGNOSIS AND TESTING
Accessory Drive
Inspection and Verification
1. Verify customer concern by running the engine.
2. Inspect the drive belt for chunking, fraying and wear.
3. Check the drive belt for correct routing.
Drive Belt Cracking/Chunking/Wear
V Ribbed Serpentine Drive Belt With Cracks Across Ribs
The accessory drive:
zhas a single serpentine drive belt.
z has an automatic drive belt tensioner.
z does not require adjustment.
V Ribbed Belt With Chunks of Rib Missing
Symptom Chart SECTION 303-
05: Accessory Drive 2003 Mustang Workshop Manual Klj . 1 ba
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Component Tests
Drive Belt Noise/Flutter
Drive belt chirp occurs due to pulley misalignment or excessive pulley runout. It can be the result of a
damaged pulley or an incorrectly aligned pulley.
To correct, determine the area where the noise comes from. Check each of the pulleys in that area
with a straightedge to the crankshaft pulley, looking for accessory pulleys out of position in the fore/aft
direction or at an angle to the straightedge.
Drive belt squeal is an intermittent noise that occurs when the drive belt slips on a pulley during certain
conditions, such as: engine start up, rapid engine acceleration, or A/C clutch engagement.
Drive belt squeal can occur:
zif any of the accessories are damaged, have a worn or damaged bearing, internal torsional
resistance above normal. All accessories should be rotatable by hand in the unloaded condition.
If not, inspect the accessory.
z if fluid gets on the drive belt. This includes power steering fluid, engine coolant, engine oil or air
conditioning system lubricant. If fluid does get on the drive belt during service, clean the drive
belt with soap and water and thoroughly rinse with clean water.
z NOTE: The drive belt tensioner arm should rotate freely without binding.
if the drive belt is too long. A drive belt that is too long will allow the drive belt tensioner arm to
go all the way to the arm travel stop under certain load conditions, which will release tension to
the drive belt. If the drive belt tensioner indicator is outside the installation wear range window,
install a new drive belt.
z if the drive belt tensioner is worn or damaged.
Belt Tension
NOTE: Drive belt tension is not adjustable.
The drive belt tensioner automatically adjusts drive belt tension. Symptom Chart Condition
Possible Sources Action
z Drive belt
noise, chirping,
flutter z
Defective/worn drive
belt.
z Misaligned pulley.
z Pulley runout.
z Damaged
accessories.
z Fluid contamination
of drive belt. z
GO to Component Tests, Drive
Belt, Noise/Flutter.
z Damaged or worn
drive belt tensioner. z
GO to Component Tests, Belt
Tensioner, Automatic.
z Premature
drive belt wear z
Defective drive belt.
z Misaligned pulley.
z Pulley runout.
z Damaged
accessories.
z Incorrectly installed
drive belt. z
GO to Component Tests, Drive
Belt Noise/Flutter and Drive
Belt Misalignment diagnosis. Klj . 2 ba
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Belt Tensioner, Automatic
Check the automatic drive belt tensioner:
1. With the engine off, check for correct drive belt routing; refer to Accessory Drive . Repair as
necessary.
2. Rotate the drive belt tensioner and check for a binding or frozen condition. Install new components as necessary.
Drive Belt Misalignment
CAUTION: Incorrect drive belt installation will cause excessive drive belt wear and may
cause the drive belt to come off the drive pulleys.
Non- standard drive belts may track differently or incorrectly. If a drive belt tracks incorrectly, install it
with an original equipment drive belt to avoid performance failure or loss of drive belt.
With the engine running, check drive belt tracking. If the (A) edge of the drive belt rides beyond the
edge of the pulleys, noise and premature wear may occur. Make sure the (B) drive belt rides correctly
on the pulley. If a drive belt tracking condition exists, proceed with the following:
zVisually check the drive belt tensioner for damage, especially the mounting pad surface. If the
drive belt tensioner is not installed correctly, the mounting surface pad will be out of position.
This will result in chirp and squeal noises.
z With the engine running, visually observe the grooves in the pulleys (not the pulley flanges or
the pulley forward faces) for excessive wobble. Install new components as necessary.
z Check all accessories, mounting brackets and the drive belt tensioner for any interference that
would prevent the component from mounting correctly. Correct any interference condition and
recheck the drive belt tracking.
z Tighten all accessories, mounting brackets, and drive belt tensioner retaining hardware to
specification. Recheck the drive belt tracking. Klj . 3 ba
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Symptom Chart
Pinpoint Tests
PINPOINT TEST A: THE ENGINE DOES NOT CRANK AND THE
RELAY DOES CLICK
SYMPTOM CHART Condition
Possible Sources Action
z The engine does
not crank and the
relay does click z
Battery.
z Fuse.
z Starter
motor/solenoid.
z Ignition switch.
z Circuit. z
Go To Pinpoint Test A .
z The engine does
not crank and the
relay does not
click z
Fuse.
z Battery.
z Starter relay.
z Ignition switch.
z Digital transmission
range (TR) sensor.
z Starter solenoid.
z Clutch pedal
position (CPP)
switch.
z Circuit. z
Go To Pinpoint Test B .
z The engine
cranks slowly z
Battery.
z Starter
motor/solenoid.
z Circuit. z
Go To Pinpoint Test C .
z Unusual starter
noise z
Starter motor
mounting.
z Starter motor.
z Incorrect starter
drive engagement. z
Go To Pinpoint Test D .
z The starter spins
but the engine
does not crank z
Starter Motor zINSPECT the starter motor
mounting and engagement.
REPAIR as necessary.
z Damaged
flywheel/ring gear
teeth. z
INSPECT the flywheel/ring
gear for damaged, missing or
worn teeth. REPAIR as
necessary. Test Step Result / Action to Take
A1 CHECK THE VOLTAGE TO THE STARTER RELAY
z
Measure the voltage between the starter relay pin 30,
circuit 1050 (LG/VT) and ground. Yes
GO to
A2 .
No
REPAIR circuit 1050 (LG/VT) Klj . 2 ba
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PINPOINT TEST B: THE ENGINE DOES NOT CRANK AND THE
RELAY DOES NOT CLICK
Test Step Result / Action to Take
B1 CHECK CIRCUIT 33 (WH/PK) FOR VOLTAGE
z
Disconnect: Starter Motor Relay.
z Key in START position.
z Measure the voltage between the starter motor relay pin 85,
circuit 33 (WH/PK) and ground while holding the key in the
START position.
z Is the voltage greater than 10 volts? Yes
GO to
B10 .
No
For automatic
transmissions, GO to
B2 . For manual
transmissions, GO to
B5 .
B2 CHECK CIRCUIT 32 (RD/LB) FOR VOLTAGE AT THE DIGITAL
TR SENSOR z
Key in OFF position.
z Disconnect: Digital TR Sensor C110.
z Key in START position.
z Measure the voltage between the digital TR sensor C110 pin
10, circuit 32 (RD/LB) and ground while holding the key in the
START position.
z Is the voltage greater than 10 volts? Yes
GO to
B3 .
No
GO to B7 .
B3 CHECK CIRCUIT 33 (WH/PK) FOR OPEN
z
Key in OFF position.
z Measure the resistance between the digital TR sensor C110 pin Yes
GO to
B4 .
No
REPAIR circuit 33
(WH/PK). TEST the
system for normal
operation. Klj . 4 ba
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PINPOINT TEST C: THE ENGINE CRANKS SLOWLY
PINPOINT TEST D: UNUSUAL STARTER NOISE z
Measure the resistance between the starter motor relay pin 86,
circuit 1205 (BK) and ground.
z Is the resistance less than 5 ohms? Test Step Result / Action to Take
NOTE:
Before beginning this test, be sure that the battery is tested and fully charged. C1 CHECK THE VOLTAGE TO THE STARTER
z
Key in OFF position.
z Measure the voltage between the starter motor
solenoid positive terminal and ground.
z Is the voltage 12.5 volts or greater? Yes
GO to
C2 .
No
REPAIR the circuit between the
battery and the starter solenoid.
CLEAN and TIGHTEN the
connections at the battery terminals.
TEST the system for normal
operation. C2 CHECK MOTOR GROUND CIRCUIT
z
Carry out the Motor Ground Circuit test; refer to
Component Tests in this section.
z Is the ground OK? Yes
INSTALL a new starter motor.
REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L . TEST the
system for normal operation.
No
REPAIR the ground circuit as
necessary. TEST the system for
normal operation. Test Step Result / Action to Take
D1 CHECK THE STARTER MOTOR
MOUNTING z
Inspect the starter motor mounting Yes Klj . 7 ba
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reading is still greater than 0.5 volts when checked at the M-
terminal and less than 0.5 volts
when checked at the B- terminal, the concern is in the solenoid contacts. Install a new starter
motor. Refer to Starter Motor — 3.8L or
Starter Motor — 4.6L .
9. Clean the positive (+) battery cable connections. Repeat the test at the starter solenoid B terminal. If the voltage is greater than 0.5 volts, install a new positive battery cable.
Starter Motor— Ground Circuit
A slow cranking condition can be caused by resistance in the ground or return portion of the cranking
circuit. Check the voltage drop in the ground circuit as follows:
1. Connect the Digital Multimeter positive lead to the starter motor housing (the connection must be clean and free of rust or grease). Connect the negative lead to the negative (- ) battery
terminal.
2. Engage the remote starter switch. Read and record the voltage. The voltage reading should be less than 0.3 volts.
3. If the voltage is greater than 0.3 volts, clean the negative cable connections at the battery, body ground connections, and the starter ground connections. Retest.
4. If the voltage is greater than 0.3 volts, install a new cable. If the voltage reading is less than 0.2 volts and the engine still cranks slowly, install a new starter motor. Refer to Starter Motor — 3.8L
or
Starter Motor — 4.6L . Item Part Number Description
1 105-
R0057 Digital multimeter
2 10653 Battery
3 — S-
terminal 4 — M-
terminal 5 — B-
terminal 6 — Remote starter switch Klj . 10 ba
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DESCRIPTION AND OPERATION
Intake Air Distribution and Filtering —
Supercharger,
Charge Air Cooler
The supercharger (SC) is a positive displacement pump. Its purpose is to supply an excess volume of
intake air to the engine by increasing air pressure and density in the intake manifold. The supercharger
is matched to the engine by its displacement and belt ratio, and can provide excess airflow at any
engine speed.
NOTE: The supercharger is repaired only as an assembly. Disassembly of the supercharger unit may
void the warranty.
NOTE: The supercharger is not a bolt- on option. It is part of an integrated engine system. Many
components of the supercharged engine are not interchangeable with similar parts from a non-
supercharged engine.
The supercharger contains two three- lobed rotors. The helical shape and specialized porting provide a
smooth discharge flow and low level of noise during operation. The rotors are supported by ball
bearings in front and needle bearings at the rear. The drive gears are pressed into place, therefore the
supercharger is installed new as a unit, and is not repairable.
The supercharger system is a blow- through type with the fuel injected directly into the intake ports. The
supercharger is belt driven off the crankshaft through an idler pulley. The throttle body controls the
amount of intake air to the supercharger through the intake plenum. Air from the supercharger is
routed through the charge air cooler (CAC), then to the intake manifold. The resulting denser air
charge in the combustion chamber provides for a higher power output of the engine over a non-
supercharged engine of the same displacement.
NOTE: It is not possible to increase manifold pressure or engine power output by altering the bypass
valve or the actuator.
At partial- throttle opening or when vacuum is present in the intake system, a vacuum- controlled
bypass valve reroutes some discharged air from the supercharger back through the intake plenum.
This prevents the supercharger from cavitating, causing reduced performance, increased
temperatures, and poor fuel economy.
The supercharger has a self- contained oiling system that does not require a fluid change for the life of
the vehicle. However, at every 30,000 mile interval, the supercharger fluid level should be checked.
The vehicle should be parked on a level surface, the engine cool, and not running. To check the oil,
remove the Allen head plug located at the front of the supercharger. The oil level should be at the
bottom of the fill plug threads when cold. If the fluid level is low, add Synthetic Supercharger Fluid
E9SZ- 19577- A or equivalent meeting Ford specification ESE-M99C115–A
Supercharged vehicles are equipped with a charge air cooler (CAC). The CAC cools the pressurized
air from the supercharger, increasing the air density, which improves combustion efficiency, engine
horsepower and torque. SECTION 303-
12: Intake Air Distribution and Filtering 2003 Mustang Workshop Manual Klj . 1 ba
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Principles of Operation
Evaporative Emission (EVAP) Canister Purge Valve
The EVAP canister purge valve is controlled by the powertrain control module (PCM). The EVAP
canister purge valve controls the flow of fuel vapors from the EVAP canister to the engine intake
manifold during various engine operating modes. The EVAP canister purge valve is normally closed.
Evaporative Emission (EVAP) Canister
Fuel vapors from the fuel tank are stored in the EVAP canister. When the engine is running, the vapors
are purged from the EVAP canister for combustion.
Canister Vent Solenoid
During the Evaporative Emission (EVAP) System Test Monitor, Evaporative Emissions Repair
Verification Drive Cycle, and the Evaporative Emission System Leak Test, the canister vent solenoid is
closed to allow a vacuum to be drawn on the fuel tank at a specific level. The canister vent solenoid is
normally open.
Fuel Tank Pressure (FTP) Sensor
The fuel tank pressure sensor is used to measure the fuel tank pressure during the Evaporative
Emissions Monitor Test. The fuel tank pressure sensor is mounted in the fuel vapor control valve tube
as it crosses over the fuel tank.
Fuel Vapor Control Valve
The fuel vapor control valve is normally between the EVAP canister and the fuel vapor vent valve. Its
function is to prevent the flow of liquid fuel into the EVAP canister or up to the canister purge valve
during refueling, and to prevent the collection of liquid fuel in the fuel vapor hoses by overfilling the fuel
tank.
Fuel Vapor Vent Valve (FVV) Assembly
The fuel vapor vent valve (FVV) assembly is mounted on the top of the fuel tank. It is used to control
the flow of fuel vapors entering the EVAP system. The head portion of the assembly prevents the fuel
tank from overfilling during refueling. The assembly also has a spring float, which prevents liquid fuel
from entering the vapor delivery system under severe handling or vehicle rollover conditions. In the
upright position, the open bottom of the float will lift and shut off the orifice. Under severe handling
conditions, the spring will push the float closed when angles allow liquid fuel to reach the orifice. In a
rollover condition, the weight of the open bottom float and spring pressure will close the orifice.
Fuel Filler Pipe Check Valve
The fuel filler pipe check valve is an intricate part of the fuel filler pipe. It is intended to prevent liquid
fuel from re-entering the fuel filler pipe from the fuel tank on refueling or roll over conditions.
Fuel Filler Cap
The fuel filler cap is used to prevent fuel spill and to close the EVAP system to the atmosphere.
Evaporative Emission System Monitor
When a fault occurs, the EVAP system monitor is reset to NO and a diagnostic trouble code (DTC) is
set in the PCM memory. After the DTC is repaired, the vehicle drive cycle must be completed to reset
the monitor in preparation for inspection and maintenance testing. EVAP Emission System Leak Test Klj . 2 ba
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To start the testing, conditions of stable purging and vehicle speed must be satisfied. During the first
stage, the canister vent solenoid is closed, while the EVAP canister purge valve remains open,
applying and building vacuum in the system as indicated by the FTP sensor. This phase checks for
major leaks in the EVAP system.
In the second stage, the EVAP canister purge valve closes and the system looks for minimal decay
rate in the EVAP vacuum, indicating the absence of any small EVAP system leaks.
The last stage is entered only if stage two of the leak test has failed and checks whether the failed test
was due to excess vapor generation. It monitors fuel vapor generation rate. Initially, the canister vent
solenoid is opened to equalize EVAP system pressure to atmosphere. Then the canister vent solenoid
is closed, allowing pressure to build if vapor generation is present in sufficient quantity. If the rate of
generation is found to be too high, the EVAP running loss system leak test is aborted. If not, then a
small leak is diagnosed.
On-
Board Refueling Vapor Recovery (ORVR) Evaporative Emission (EVAP) System
The basic elements forming the ORVR system are as follows:
zThe fuel filler pipe forms a seal to prevent vapors from escaping the fuel tank while liquid is
entering the fuel tank. Liquid in the one inch diameter tube blocks vapors from rushing back up
the fuel filler pipe.
z A fuel vapor control valve controls the flow of vapors out of the fuel tank. The valve closes when
the liquid level reaches a height associated with fuel tank usable capacity. The valve
accomplishes the following:
„limits the total amount of fuel that can be dispensed into the fuel tank
„ prevents liquid gasoline from exiting the fuel tank when submerged (as well as when
tipped well beyond a horizontal plane as part of the vehicle rollover protection in road
accidents)
„ minimizes vapor flow resistance during anticipated refueling conditions
z Fuel vapor tubing connects the fuel vapor control valve to the EVAP canister. This routes the
fuel tank vapors, displaced by the incoming liquid, to the EVAP canister.
z A check valve in the fuel filling system prevents liquid from rushing back up the fuel filler pipe
during the liquid flow variations associated with the filler nozzle shut- off.
Between refueling events, the EVAP canister is purged with fresh air so that it may be used again to
store vapors accumulated during engine soaks or subsequent refueling events. The vapors drawn off
of the carbon in the EVAP canister are consumed by the engine.
Inspection and Verification 1. Verify the customer concern is with the evaporative emission (EVAP) system.
2. Visually inspect for the following obvious signs of mechanical damage.
Visual Inspection Chart Mechanical
z
Fuel filler cap
z EVAP test port
z EVAP canister or canister vent solenoid Klj . 3 ba
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