EVAP Canister Purge Valve Inspection
Caution: Do not breathe the air through the EVAP component tubes
or hoses. The fuel vapors inside the EVAP components may cause personal injury.
- Remove the EVAP canister purge valve. Refer to
Evaporative Emission Canister Purge Solenoid Valve Replacement
.
- Use a DMM in order to measure the resistance of the EVAP canister
purge valve.
Measure
The EVAP canister purge valve resistance should be 27-33 ohms
at 20°C (68°F).
- Replace the EVAP canister purge valve if the resistance is not
within the specified range. The solenoid will damage the PCM if the resistance
value is less than 27 ohms.
- Check the PCM and replace if necessary. Refer to
Powertrain Control Module Replacement
.
- Check for continuity of
each terminal to the valve body.
- Replace the EVAP canister purge valve if continuity is present.
- Blow air into the inboard
port (1). The air should NOT flow through the outboard port (2).
- Apply battery voltage across the terminals of the EVAP canister
purge valve.
- Blow air into the inboard port (1). The air should flow
easily to the outboard port (2).
- Replace the EVAP canister purge valve if the valve failed either
test. Refer to
Evaporative Emission Canister Purge Solenoid Valve Replacement
.
EVAP Pressure Switching Solenoid Inspection
Caution: Do not breathe the air through the EVAP component tubes
or hoses. The fuel vapors inside the EVAP components may cause personal injury.
- Remove the EVAP pressure
switching solenoid.
- Use a DMM in order to measure the resistance of the EVAP pressure
switching solenoid.
Measure
The EVAP pressure switching solenoid resistance is 37-44 ohms
at 20°C (68°F).
- Replace the EVAP pressure switching solenoid if the resistance
is not within the specified range. The solenoid will damage the PCM, if the
resistance value is less than 27 ohms.
- Check for continuity on
each terminal to the valve body.
- Replace the EVAP pressure switching solenoid if continuity is
present.
- Blow air into the inboard
port (1). The air should NOT flow through the valve and out of the
outboard port (2).
- Apply battery voltage across the terminals of the EVAP pressure
switching solenoid.
- Blow air into the inboard port (1) and air should flow
through the valve and out of the outboard port (2).
- Replace the EVAP pressure switching solenoid if the solenoid failed
either test.
EVAP Canister Vent Valve Inspection
Caution: Do not breathe the air through the EVAP component tubes
or hoses. The fuel vapors inside the EVAP components may cause personal injury.
- Disconnect the EVAP vent solenoid electrical connector.
- Use a DMM in order the measure the solenoid resistance value.
Measure
The resistance should be between 25-30 ohms at 20°C
(68°F).
- Replace the solenoid if the resistance is not within the specified
range. Refer to
Evaporative Emission Canister Vent Solenoid Valve Replacement
.
- Use a DMM in order the
check for continuity between each solenoid terminal and solenoid housing.
Measure
The DMM has to read infinite (OL).
- Replace the EVAP vent solenoid valve if the resistance is not
within specification. A shorted valve will cause damage to the PCM.
- Blow air through the
inboard port (2) of the EVAP vent valve. Air has to flow freely through
the outboard port (1).
- Replace the valve if the air does not flow through the inboard
port (2). Refer to
Evaporative Emission Canister Vent Solenoid Valve Replacement
.
- Apply battery voltage
across the solenoid terminals.
- Blow air through the inboard port (1) of the solenoid.
Air should NOT flow through the valve.
- Replace the solenoid if the solenoid fails any of the tests. Refer
to
Evaporative Emission Canister Vent Solenoid Valve Replacement
.
Fuel Tank Pressure (FTP) Sensor Inspection
Tools Required
J 23738-A Hand Vacuum
Pump
- Disconnect the electrical
connector (4) from the fuel tank pressure (FTP) sensor .
- Turn ON the ignition, with the engine OFF.
- Measure the voltage between the 5 volt reference circuit (2)
and the sensor ground circuit (1) with a DMM.
Measure
The DMM should read 5.0 volts.
- If the measured voltage is not 5.0 volts for both tests,
inspect for the following conditions:
• | An open or a high resistance in the 5 volt reference circuit
of the fuel tank pressure sensor . |
• | An open or high resistance in the ground circuit of the fuel tank
pressure sensor . |
- Measure the voltage from
the input circuit (1) of the fuel tank pressure sensor to ground with
the DMM.
Measure
The DMM should read 4.5-5.5 volts.
- If the measured voltage is not 4.5-5.5 volts inspect
for the following conditions:
• | An open or high resistance in the input circuit of the fuel tank
pressure sensor . |
• | A short in the input circuit of the fuel tank pressure sensor. |
- Turn OFF the ignition.
- Connect the electrical connector to the fuel tank pressure sensor
.
- Disconnect the vacuum hose to the fuel tank pressure sensor.
- Connect a hand held vacuum/pressure pump to the fuel tank pressure
sensor.
- Select the DC scale on the DMM.
- Connect one lead to the input circuit at C221 of the fuel tank
pressure sensor , and connect the other lead to ground.
- Measure the output voltage under the following conditions:
• | Apply vacuum of 2.0 kPa (15 mm Hg, 0.59 in. Hg)
to the fuel tank pressure sensor. |
Measure
1.3-2.1 volts
• | Release the vacuum from the fuel tank pressure sensor. |
Measure
3.0-3.6 volts
• | Apply a pressure of 1.5 kPa (0.22 psi) to the fuel tank
pressure sensor. |
Measure
4.2-4.8 volts
- Replace the fuel tank pressure sensor if the measured voltage
is not within the test values listed above. Refer to
Fuel Tank Pressure Sensor Replacement
.
- Remove the hand held vacuum pump.
- Connect the vacuum hose to the fuel tank pressure sensor .
EVAP Canister Inspection
Tools Required
J 23738-A Hand Vacuum
Pump
Caution: Do not breathe the air through the EVAP component tubes
or hoses. The fuel vapors inside the EVAP components may cause personal injury.
- Remove the EVAP canister. Refer to
Evaporative Emission Canister Replacement
.
- Plug the port (4).
- Hold the port plugged through the all tests.
- Hold the port (5) closed.
- Blow air with a pressure of 1.7 kPa (0.5 in Hg/0.25 psi)
into port (1).
- Verify that air flows out of port (2).
- Hold the port (5)
and the port (2) closed.
- Blow air with a pressure of 1.7 kPa (0.5 in Hg/0.25 psi)
into port (1).
- Verify that air does not flow out of the port (3).
- Hold the port (3)
closed.
- Apply a vacuum of 3.5 kPa (1.0 in Hg/0.5 psi)
to port (5).
- Verify that the vacuum holds if the port (3) is closed.
- Open the port (3) and check for vacuum release.
- Hold the port (3)
closed and apply 3.5 kPa (1.0 in. Hg/0.5 psi)
of vacuum to port (1) .
- Check that air flows into the port (5).
- Replace the EVAP canister if the EVAP canister purge valve failed
the above tests.
- Remove the plug from the EVAP port.
- Install the EVAP canister. Refer to
Evaporative Emission Canister Replacement
.
EVAP System Inspection
- Visually inspect the EVAP
lines, the hoses, and the connection for the following:
• | Any sharp bends or kinks |
• | Any deformed lines and hoses |
• | Any incorrect routing of lines and hoses |
- Repair or replace any lines and hoses as necessary.
- Inspect the fuel filler cap gasket for damage.
- Visually inspect the EVAP
canister for cracks.
- Replace the EVAP canister if the canister is damaged. Refer to
Evaporative Emission Canister Replacement
.