Isuzu 1999 RODEO Workshop Manual page 1568

Step
1 Was the "On-Board Diagnostic (OBD) System Check"
performed?
2 Is DTC P0442 or P0446?
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?
4 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 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?
6 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?
7 1. Visually/physically
conditions:
f
Restricted fuel tank vapor line.
f
Restricted EVAP purge line.
2. If a problem is found, repair as necessary.
Was a problem found?
RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS
DTC P0440 – EVAP System
Action
check for the following
Value(s) Yes
— Go to Step 2
Go to other
DTC (P0442
— or P0446)
1.51V Go to Step 4
5 in. H2O Go to Step 5
1.47 – 1.51V Go to Step 8
Go to Step 11
5 in. Hg
— Go to Step 16
6E2–325
No
Go to OBD
System
Check
Go to Step 3
Go to
DTCP0452 or
P0453
Go to Step 6
Go to Step 7
Go to Step 10
Go to
DTCP0452 or
P0453