2003 FORD MUSTANG check engine

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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PINPOINT TEST D: HISSING SOUND WHEN REMOVING FUEL CAP z
Pressurize the EVAP system to 3.48 kPa (14
inches H
2 O).
z Does the pressure drop immediately? GO to
Pinpoint Test D .
C3 CHECK FOR BLOCKAGE BETWEEN THE FUEL
FILLER PIPE AND THE FUEL VAPOR TEE z
Connect the Evaporative Emission System Leak
Tester to the fuel filler pipe.
z Pressurize the EVAP system to 3.48 kPa (14
inches H
2 O).
z Does the pressure drop immediately? Yes
GO to
C4 .
No
GO to Pinpoint Test D .
C4 CHECK FOR FUEL TANK PRESSURE SENSOR
PID WITHOUT PRESSURE APPLIED z
Disconnect the EVAP canister outlet tube at the
EVAP canister.
z Key in ON position.
z Access PCM PID FTP V.
z Record the reading.
z Is PID FTP V reading between 2.40 and 2.80
volts? Yes
GO to
C5 .
No
REFER to Powertrain
Control/Emissions Diagnosis (PC/ED)
manual to continue diagnosis. C5 CHECK FOR STUCK OPEN EVAP CANISTER
PURGE VALVE CONDITION AT IDLE z
Connect the EVAP canister outlet tube.
z Remove the plug from the EVAP return tube and
reconnect the tube to the intake manifold.
z Verify that the fuel filler cap is correctly installed.
z Key in ON position.
z Access PCM PIDs FTP V and EVAPPDC.
z Start the engine and allow to idle.
z Monitor the FTP V and EVAPPDC PIDs.
z When PID EVAPPDC is zero, is PID FTP V
reading below 2.40 volts? Yes
INSTALL a new EVAP canister purge
valve. REFER to
Evaporative Emission Canister Purge Valve in this section.
CARRY OUT an EVAP system leak
test. REFER to Evaporative Emission System Leak Test in this section. If the
system passes the leak test, CARRY
OUT an evaporative emissions repair
verification drive cycle. REFER to
Evaporative Emission Repair Verification Drive Cycle in this section.
No
CARRY OUT the EVAP system leak
test. REFER to Evaporative Emission System Leak Test in this section. If the
system passes the leak test, CARRY
OUT the evaporative emissions repair
verification drive cycle. REFER to
Evaporative Emission Repair Verification Drive Cycle in this section. Klj . 11 ba
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are mandatory when proceeding through the following drive cycle.
7. NOTE: This step allows engine warm- up and provides intake air temperature (IAT) input to the
PCM.
Idle the vehicle for 15 seconds. Drive at 64 km/h (40 mph) until the ECT is at least 76.7°C (170°
F).
8. Is IAT above 4.4°C (40°F) and below 37.8°C (100°F)? If not, continue with the following steps but note that the EVAP Monitor Bypass portion of the drive cycle (Step 13) will be required to
bypass the EVAP monitor and clear the P1000.
9. NOTE: This step executes the heated oxygen sensor (HO2S) monitor.
Cruise at 64 km/h (40 mph) for 60 seconds.
10. NOTE: This executes the EVAP monitor if IAT is above 4.4°C (40°F) and below 37.8°C (100°F).
NOTE: To initiate the monitor, TP MODE should equal PT, EVAPDC must be greater than 75%,
and FLI must be between 15 and 85%.
NOTE: Avoid sharp turns and hills.
Cruise at 72 to 104 km/h (45 to 65 mph) for 10 minutes.
11. NOTE: This step executes the ISC portion of the Secondary Air/CCM.
Bring the vehicle to a stop. Idle with the transmission in DRIVE (for automatic transmission) or
NEUTRAL (for manual transmission) for two minutes.
Pending Code and EVAP Monitor Bypass Check
12. NOTE: This determines if a pending code is preventing the clearing of P1000.
NOTE: If the EVAP monitor is not complete and IAT was below 4.4°C (40°F) or above 37.8°C
(100°F) temperature range in Step 8, or the altitude is above 2,438 meters (8,000 feet), the
EVAP Monitor Bypass (Step 13) must be carried out.
Using the scan tool, check for pending codes. Conduct normal repair procedures for any
pending code concerns. Rerun any incomplete monitor.
EVAP Monitor Bypass
13. NOTE: This allows the bypass counter to increment to two.
NOTE: Do not repeat Step 4.
Park the vehicle for a minimum of eight hours. Repeat Steps 5 through 12. Klj . 2 ba
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SPECIFICATIONS
a
MERCON® V is not interchangeable at this time with the current MERCON® fluids. Check the
transmission fluid level indicator to determine the correct fluid and refer to the Workshop/Owner
publication to determine the correct service interval for the specific vehicle. SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual General Specifications
Item Specification
Fluid
a Motorcraft MERCON® V Transmission Fluid XT
-5-QM MERCON®
V Fluid Capacities
3.8L engine 13.2L (13.9 quarts)
4.6L engine 12.0L (12.8 quarts)
Fluid Filter
Inline Transmission Fluid Filter Kit XC3Z-
7B155- AA Inline Transmission Fluid Filter XC3Z-
7B155- BA Lubricant
Ford Multi-Purpose Grease D0AZ-19584-
AA ESB-
M1C93- B
Torque Converter End Play Item Specification
New or remanufactured 0.355-
1.04 mm (0.014- 0.074 in) Used 0.355-
1.87 mm (0.014- 0.074 in)
Band and Clutch Application Chart Gear Overdrive
Band Low
Reverse Band Forward
Clutch Direct
Clutch Interm
Friction Clutch Reverse
Clutch Interm
One-Way
Clutch Planetary
One- Way
Clutch 1st Gear
Manual Low A A H
2nd Gear
Manual Low A A A H
1st Gear —
(D)
(Overdrive) A H
2nd Gear —
(
D)
(Overdrive) A A H
3rd Gear —
(
D)
(Overdrive) A A A O/R
4th Gear —
(
D) A A A O/R Klj . 1 ba
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DIAGNOSIS AND TESTING
Diagnostic Strategy
Troubleshooting an electronically controlled automatic transmission is simplified by using the proven
method of diagnosis. One of the most important things to remember is that there is a definite
procedure to follow.
NOTE:
Do not take any short cuts or assume that critical checks or adjustments have already been
made.
Follow the procedures as written to avoid missing critical components or steps.
To properly diagnose a concern have the following publications available:
zTransmission Reference Manual.
z Powertrain Control/Emissions Diagnosis (PC/ED) manual.
z TSBs and OASIS Messages.
z Wiring Diagram.
These publications provide the information required when diagnosing transmission concerns.
Use the Diagnostic Flow Chart as a guide and follow the steps as indicated.
Preliminary Inspection
zKnow and understand the customer's concern.
z Verify the concern by operating the vehicle.
z Check the fluid levels and condition.
z Check for non-factory add- on items.
z Check shift linkages for proper adjustment.
z Check TSBs and OASIS messages regarding the concern.
Diagnostics
zCarry out on- board diagnostic procedures key on engine off (KOEO) and key on engine running
(KOER).
z Record all diagnostic trouble codes (DTCs).
z Repair all non- transmission codes first.
z Repair all transmission codes second.
z Erase all continuous codes and attempt to repeat them.
z Repair all continuous codes.
z If only pass codes are obtained, refer to Diagnosis By Symptom for further information and
diagnosis.
Follow the diagnostic sequence to diagnose and repair the concern the first time. SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Preliminary Inspection
The following items must be checked prior to beginning the diagnostic procedures:
Know and Understand the Concern
In order to correctly diagnose a concern, first understand the customer complaint or condition.
Customer contact may be required in order to begin to verify the concern. Understand the conditions,
including when the concern occurs. For example:
zHot or cold vehicle temperature
z Hot or cold ambient temperature
z Vehicle driving conditions
z Vehicle loaded/unloaded
After understanding when and how the concern occurs, proceed to Verification of Condition.
Verification of Condition
This section provides information that must be used in both determining the actual cause of customer
concerns and carrying out the appropriate procedures.
The following procedures must be used when verifying customer concerns for the transmission.
Determine Customer Concern
NOTE: Some transmission conditions can cause engine concerns. An electronic pressure control short
circuit can cause engine misfiring. The torque converter clutch not disengaging will stall the engine.
Determine customer concerns relative to vehicle use and dependent driving conditions, paying
attention to the following items:
zHot or cold vehicle operating temperature
z Hot or cold ambient temperatures
z Type of terrain
z Vehicle loaded/unloaded
z City/highway driving
z Upshifting
z Downshift
z Coasting
z Engagement
z Noise/vibration — check for dependencies, either rpm dependent, vehicle speed dependent,
shift dependent, gear dependent, range dependent, or temperature dependent.
Check Fluid Level and Condition
Fluid Level Check SECTION 307-
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CAUTION: The vehicle should not be driven if the fluid level indicator shows the fluid
below the DO NOT DRIVE mark or internal failure could result.
NOTE: If the vehicle has been operated for an extended period, at high highway speeds, in city traffic,
during hot weather, or while pulling a trailer, the fluid needs to cool down to obtain an accurate
reading.
NOTE: The fluid level reading on the indicator will differ from operating and ambient temperatures. The
correct reading should be within the normal operating temperature range.
Under normal circumstances the fluid level should be checked during normal maintenance. If the
transmission starts to slip, shifts slowly, or shows signs of fluid leaking, the fluid level should be
checked.
1. With the transmission in P (PARK), the engine at idle, foot pressed on the brake, move the range selector lever through each gear and allow engagement of each gear. Place the
transmission range selector lever in the P position.
2. Wipe the fluid level indicator cap and remove the indicator.
3. Wipe the indicator with a clean cloth.
4. Install the indicator back in the filler tube until it is fully seated, then remove the indicator. The fluid level should be within the normal operating temperature range.
High Fluid Level
A fluid level that is too high may cause the fluid to become aerated due to the churning action of the
rotating internal parts. This will cause erratic control pressure, foaming, loss of fluid from the vent tube,
and possible transmission failure. If an overfill reading is indicated, drain and refill the transmission.
Low Fluid Level
A low fluid level could result in poor transmission engagement, slipping, or failure. This could also
indicate a leak in one of the transmission seals or gaskets. Adding Fluid Item Description
1 Fluid level at room temperature 10°-
35°C (50°-95°F) 2 Fluid level at operating temperature 66°-
77°C (150°-170°F) 3 Do not drive mark Klj . 2 ba
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