Isuzu 2008MY N Series Workshop Manual page 83

1A-80 Engine Control System (4HK1)
Step
1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
2
4. Monitor the DTC Information with a scan tool.
Is DTC P0089, P0091, P0092, P0192, P0193,
P0201 - P0204, P2146 or P2149 set?
1. Turn OFF the ignition.
2. Place the transmission in Neutral and set the
parking brake.
3. Start the engine.
4. Accelerate the engine between idle and
3
W.O.T. (accelerator pedal full travel) many
times while observing the Fuel Rail Pressure
parameter with a scan tool.
Does the Fuel Rail Pressure parameter ever
exceed the specified value?
1. Turn OFF the ignition.
2. Wait 1 minute for the fuel pressure to bleed
down from the fuel rail.
3. Turn ON the ignition, with the engine OFF.
4
4. Observe the Fuel Rail Pressure (FRP) Sensor
parameter with the scan tool.
Does the scan tool indicate within the
specified value?
1. Start the engine.
2. Perform the Cylinder Balance Test with a scan
tool.
3. Command each injector OFF and verify an
5
engine speed change for each injector.
Is there an injector that does not change
engine speed when commanded OFF?
Action Value(s)
—
Go to Applicable
180 MPa
(26,000 psi)
Go to Step 4
0.9 to 1.0 volt
Go to Step 5
—
Go to Step 15
Yes No
DTC Go to Step 3
An intermittent
problem by foreign
material in the fuel
system is
suspected. Go to
Step 13
Go to Step 12
Go to Step 6