1991 1999 ford explorer chilton User Manual

							Evaporative canister and hose routing on the 2.3L and 2.1L engine
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HOW TO USE THIS BOOK
COMPONENT TESTING 517 
						

							Evaporative canister and hose routing on the 3.0L engine-2.4L engine similar
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518 COMPONENT TESTING 
						

							Evaporative canister and hose routing on the 4.0L engine
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HOW TO USE THIS BOOK
COMPONENT TESTING 519 
						

							EVAP canister mounting for the 1.0L engine
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520 COMPONENT TESTING 
						

							Fuel vapor management valve mounting-1.0L engine shown, others similar
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HOW TO USE THIS BOOK
COMPONENT TESTING 521 
						

							EVAP hose routing on the 1.0L engine
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Fuel Vapor Canister
Generally, the only testing done to the vapor canister is a visual inspection. Look the canister over and replace
it with a new one if there is any evidence of cracks or other damage.
Do not try to check the fuel saturation of the canister by weighing it or by the intensity of the fuel odor
from the canister. These methods are unreliable and inhaling gasoline fumes can be toxic.
CANP Solenoid
1441-1444 MODELS
Remove the CANP solenoid.
1. 
Using an external voltage source, apply 4-14 DC volts to the CANP solenoid electrical terminals.
Then, use a hand-held vacuum pump and apply 16 in. Hg (13 kPa) vacuum to the manifold side
nipple of the CANP solenoid. If the solenoid opens and allows air to freely pass through it, the solenoid is working properly.
1. 
2.  HOW TO USE THIS BOOK
522 COMPONENT TESTING 
						

							If the solenoid does not allow air to pass freely while energized, replace the solenoid with a
new one.
2. 
1441-44 MODELS Remove the CANP solenoid.
1. 
Measure the resistance between the two CANP terminals. If the resistance is between 30-40 ohms, proceed to the Step 3.
1. 
If the resistance is not between 30-40 ohms, replace the CANP solenoid.
2. 
2. 
Attach a hand-held vacuum pump to the intake manifold vacuum side of the CANP solenoid, then
apply 16 in. Hg (13 kPa) of vacuum to the solenoid. If the solenoid will not hold vacuum for at least 20 seconds replace it with a new one.
1. 
If the solenoid holds vacuum, proceed to Step 4. Keep the vacuum applied to the solenoid.
2. 
3. 
Using an external voltage source, apply 4-14 DC volts to the CANP solenoid electrical terminals. If the solenoid opens and the vacuum drops, the solenoid is working properly.
1. 
If the solenoid does not open and the vacuum remains, replace the solenoid with a new one.
2. 
4. 
REMOVAL & INSTALLATION
Fuel Vapor Canister
The fuel vapor canister is referred to as the evaporative emissions canister on 1441-44 models. Disconnect the vapor hoses from the canister.
1. 
Remove the mounting screws, then remove the canister.
2. 
To install: Position the canister in place, then install the mounting screws.
3. 
Attach all of the vapor hoses to the canister.
4. 
Fuel Vapor Valve
This component is also known as the evaporative emission valve on 1441-44 models. Disconnect the negative battery cable.
1. 
Relieve the fuel system pressure.
2. 
Remove the fuel tank.
3. 
Remove the fuel vapor valve from the fuel tank.
4. 
To install: Install the fuel vapor valve into the fuel tank.
1. 
Install the fuel tank in the vehicle.
2. 
Connect the negative battery cable.
3. 
CANP Solenoid Disconnect the vapor hoses from the CANP solenoid.
1. 
Unplug the electrical connector from the CANP solenoid.
2. 
Remove the purge solenoid valve from the vehicle.
3. 
To install: HOW TO USE THIS BOOK
COMPONENT TESTING 523 
						

							Install the CANP solenoid, then attach the engine wiring harness connector to the solenoid.
4. 
Connect the vapor hoses to the solenoid.
5. 
Pressure/Vacuum Relief Fuel Tank Filler Cap Unscrew the fuel filler cap. The cap has a pre-vent feature that allows the tank to vent for the first  3
/4
turn before unthreading.
1. 
Remove the screw retaining the fuel cap tether and remove the fuel cap.
2. 
To install: Position the end of the tether against its mounting boss, then install and tighten the tether screw.
3. 
Thread the filler cap into the fuel tank filler tube, making sure to turn it clockwise until the ratchet
mechanism gives off 3 or more loud clicks.
4. 
Exhaust Gas Recirculation (EGR) System
OPERATION
The Exhaust Gas Recirculation (EGR) system is designed to reintroduce exhaust gas into the combustion
chambers, thereby lowering combustion temperatures and reducing the formation of Oxides of Nitrogen
(NO x).
The amount of exhaust gas that is reintroduced into the combustion cycle is determined by several factors,
such as: engine speed, engine vacuum, exhaust system backpressure, coolant temperature, throttle position.
All EGR valves are vacuum operated. The EGR vacuum diagram for your particular vehicle is displayed on
the Vehicle Emission Control Information (VECI) label.
The EGR system is a Pressure Feedback EGR (PFE) or Differential PFE (DPFE) system, controlled by the
Powertrain Control Module (PCM) and composed of the following components: PFE or DPFE sensor (also
referred to as the backpressure transducer), EGR Vacuum Regulator (EVR) solenoid, EGR valve, and assorted
hoses and tubing. HOW TO USE THIS BOOK
524 REMOVAL & INSTALLATION 
						

							Typical EGR system schematic
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COMPONENT TESTING HOW TO USE THIS BOOK
OPERATION 525 
						

							Exploded view of the EGR system and related components for the 2.3L and 2.5L engine
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526 COMPONENT TESTING