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Isuzu Rodeo UE. Manual - part 392

6E2–323

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0440 EVAP System

D06RX019

Circuit Description

The evaporative system includes the following
components:

Fuel tank

EVAP canister vent solenoid

Fuel tank pressure sensor

Fuel pipes and hoses

Vapor lines

Fuel cap

Evaporative emissions canister

Purge lines

EVAP canister purge solenoid

The evaporative leak detection diagnostic strategy is
based on applying vacuum to the EVAP system and
monitoring vacuum decay. The powertrain control
module (PCM) monitors vacuum level via the fuel tank
pressure sensor input. At an appropriate time, the EVAP
canister purge solenoid and the EVAP canister vent

solenoid are turned “ON,” allowing engine vacuum to
draw a small vacuum on the entire evaporative emissions
system. If a sufficient vacuum level cannot be achieved, a
large leak or a faulty EVAP canister purge solenoid is
indicated. This can be caused by the following conditions:

Disconnected or faulty fuel tank pressure sensor

Missing or faulty fuel cap

Disconnected, damaged, pinched, or blocked EVAP
purge line

Disconnected or damaged EVAP vent hose

Disconnected, damaged, pinched, or blocked fuel tank
vapor line

Disconnected or faulty EVAP canister purge solenoid

Disconnected or faulty EVAP canister vent solenoid

Open ignition feed circuit to the EVAP canister vent
solenoid or the EVAP canister purge solenoid

Damaged EVAP canister

Leaking fuel sender assembly O-ring

Leaking fuel tank or fuel filler neck

6E2–324

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

Any of the above conditions can set DTC P0440.

Conditions for Setting the DTC

No TP sensor, ODM, IAT sensor, or MAP sensor DTCs
set.

Start-up engine coolant temperature is less than 32

(90

F).

Start-up engine coolant temperature is not more than
7

C (13

F) greater than start-up intake air

temperature.

Start-up intake air temperature is greater than 4

(39

F) .

Start-up intake air temperature is not more than 2

F) greater than start-up engine coolant

temperature.

Vehicle speed is less than 75 mph (120 km/h).

Throttle position is greater than 7% but less than 30%.

Minimal fuel slosh.

Fuel tank level is between 15% and 85%.

BARO is greater than 75 kPa.

The EVAP system is unable to achieve or maintain
vacuum during the diagnostic test.

Above conditions are present for 60 to 180 seconds.

Action Taken When the DTC Sets

The PCM will illuminate the MIL during the second key
cycle in which the DTC sets.

The PCM will store conditions which were present
when the DTC set as Freeze Frame and in the Failure
Records data.

Conditions for Clearing the MIL/DTC

The PCM will turn the MIL “OFF” when the diagnostic
has been run and the fault condition is no longer
present.

A history DTC P0440 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0440 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

Cracked or punctured EVAP canister.

Damaged or disconnected source vacuum line, EVAP
purge line, vent hose or fuel tank vapor line.

Poor connection at PCM – Inspect harness connectors
for backed-out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

Damaged harness–Inspect the wiring harness to the
EVAP canister vent solenoid, EVAP canister purge
solenoid and the fuel tank pressure sensor for an
intermittent open or short circuit.

Kinked, pinched, or plugged vacuum source, EVAP
purge, or fuel tank vapor line–Verify that the lines are
not restricted.

Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. If an EVAP canister vent solenoid or an EVAP

canister purge solenoid electrical fault is present,
the purge system will not operate correctly.
Repairing the electrical fault will very likely correct
the condition that set DTC P0440.

3. Checks the fuel tank pressure sensor at ambient

pressure.

4. Determines whether or not the EVAP system can be

sealed sufficiently to be pressurized. If not, the
large leak must be located and corrected before
continuing with diagnosis.

5. Verifies that the fuel tank pressure sensor accurately

reacts to EVAP system pressure changes.

8. Checks for a blocked EVAP canister purge solenoid.

The PCM commands the EVAP canister purge
solenoid “OFF” (open) and the vent solenoid “ON”
(closed) with the Tech 2 “System Perf.” EVAP
output control function activated. Any pressure in
the system should be released through the EVAP
canister purge solenoid within a few seconds when
“System Perf.” is activated.

9. Ensures that sufficient source vacuum is present at

the EVAP canister purge solenoid.

6E2–325

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0440 – EVAP System

Step

Action

Value(s)

Yes

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to

Step 2

Go to

OBD

System

Check

Is DTC P0442 or P0446?

—

Go to

other

DTC (P0442

or P0446)

Go to

Step 3

1. Ignition “OFF.”
2. Remove the fuel cap.
3. Ignition “ON.”
4. Observe “Fuel Tank Pressure” on the Tech 2.

Does the Tech 2 indicate “Fuel Tank Pressure” at the
specified value?

1.51V

Go to

Step 4

Go to

DTCP0452 or

P0453

IMPORTANT: Before continuing with diagnosis, zero
the EVAP pressure and vacuum gauges on the EVAP
pressure/purge cart J 41413 (refer to tool operating
instructions).

1. Replace the fuel cap.
2. Capture Failure Records data for DTC P0440 and

clear DTCs.

3. Using the Tech 2, command the EVAP canister vent

solenoid “ON” (closed).

4. Connect the EVAP pressure/purge cart J 41413 to

the EVAP service port.

5. Attempt to pressurize the EVAP system using the

EVAP pressure/purge cart J 41413 (monitor
pressure using gauge on cart).

Can EVAP system be pressurized to specified value?

5 in. H2O

Go to

Step 5

Go to

Step 6

1. Maintain fuel tank pressure at 5 inches at H2O.
2. Observe “Fuel Tank Vacuum” on the Tech 2.

Does Tech 2 indicate “Fuel Tank Vacuum” at the
specified value?

1.47 – 1.51V

Go to

Step 8

Go to

Step 7

1. Disconnect the fuel tank vapor line and the EVAP

purge line from the EVAP canister.

2. Block the canister fitting for the fuel tank vapor line.
3. Connect a hand vacuum pump to the canister fitting

for the EVAP purge line.

4. Ensure that the EVAP canister vent solenoid is still

commanded “ON” (closed).

5. Attempt to apply vacuum to the EVAP canister.

Can the vacuum be maintained at the specified value?

5 in. Hg

Go to

Step 11

Go to

Step 10

1. Visually/physically check for the following

conditions:

Restricted fuel tank vapor line.

Restricted EVAP purge line.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Go to

Step 16

Go to

DTCP0452 or

P0453

6E2–326

RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0440 – EVAP System

(Cont'd)

Step

Yes

Value(s)

Action

1. Disconnect the vacuum source line at the EVAP

canister purge solenoid and plug the vacuum
source fitting on the solenoid.

2. Using the Tech 2 output tests function, select

“System Perf.” and activate.

3. Pressurize the EVAP system to the specified value

5 in. H2O (monitor pressure using gauge on cart).

4. Observe the EVAP pressure gauge on the EVAP

pressure/purge cart J 41413 while removing the
plug from the EVAP canister purge solenoid.

Does “Fuel Tank Pressure” decrease to the specified
value within 15 seconds while “System Perf.” is
activated?

0 in. H2O

Go to

Step 9

Go to

Step 13

1. Connect the in. Hg vacuum gauge on the EVAP

pressure/purge cart J 41413 to the vacuum source
line.

2. Ignition “ON,” engine idling.
3. Run the engine above 2000 RPM and and observe

source vacuum level (monitor vacuum using gauge
on cart).

Does source vacuum level exceed the specified value?

15 in. Hg

Refer to

Diagnostic

Aids

Go to

Step 14

1. Visually/physically check for the following

conditions:

Vent hose disconnected or the damaged.

EVAP canister damaged.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Go to

Step 16

Go to

Step 15

1. Visually/physically check for the following

conditions:

Missing or faulty fuel cap.

Disconnected or leaking fuel tank vapor line.

Disconnected or damaged EVAP purge line.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Go to

Step 16

Go to

Step 12

1. Using Tech 2, command the EVAP canister vent

solenoid “ON” (closed).

2. With the cart connected to the EVAP service port,

continuously attempt to pressurize the EVAP
system by leaving the cart control knob in the
pressurize position.

3. Using ultrasonic leak detector J 41416, locate and

repair leak in EVAP system. (It may be necessary to
partially lower the fuel tank to examine the
connections on top of the tank.)

Is the action complete?

—

Go to

Step 16

—

Replace the EVAP canister purge solenoid.

Is the action complete?

—

Go to

Step 16

—

Locate and repair cause of no source vacuum to the
EVAP canister purge solenoid.

Is the action complete?

—

Go to

Step 16

—

Content .. 390 391 392 393 ..