Verify Repair Go To Step; Was The "On-Board Diagnostic (Obd) System Check" Performed - Isuzu C22NE Workshop Manual

Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Located on the intake manifold which is at the top
right part of the engine.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Step
Was the "On-Board Diagnostic (OBD) System
1 Check" performed?
1. Turn the ignition OFF.
2. Turn the air conditioning system OFF.
3. Relieve fuel system pressure and install the fuel
pressure gauge.
4. Turn the ignition ON.
2
Note: The fuel pump will run for approximately 2 seconds.
Use the Scan Tool to command the fuel pump ON.
5. Observe the fuel pressure indicated by the fuel pressure
gauge with the fuel pump running.
Is the fuel pressure within the specified limits?
Does the fuel pressure indicated by the fuel pressure
gauge remain constant?
3
Note: The fuel pressure will drop when the fuel pump
stops running, then it should stabilize and remain constant.
1. When the vehicle is at normal operating temperature,
turn the ignition ON to build fuel pressure and observe
the measurement on the gauge.
4
2. Start the engine and observe the fuel pressure gauge.
Did the reading drop by the amount specified after the
engine was started?
Is fuel pressure dropping off during acceleration, cruise, or
5 hard cornering?
Visually and physically inspect the following items for a
restriction:
• The in-pipe fuel filter.
6
• The fuel feed line.
Was a restriction found?
Remove the fuel tank and visually and physically inspect
the following items:
• The fuel pump strainer for a restriction.
7
• The fuel line for a leak.
• Verify that the correct fuel pump is in the vehicle.
Was a problem found in any of these areas?
Fuel System Diagnosis
Action
DRIVEABILITY AND EMISSIONS 6E1-119
Fuel Pressure Gauge Installation
1. Remove the shoulder fitting cap.
2. Install fuel pressure gauge 5-8840-0378-0 to the
fuel feed line located on the upper right side of the
engine.
3. Reinstall the fuel pump relay.
Value(s)
-
283-376 kPa
(41-55 psi)
-
21-105 kPa
(3-15 psi)
-
-
-
Yes No
Go to OBD
System
Go to Step 2 Check
Go to Step 3 Go to Step 17
Go to Step 4 Go to Step 12
Go to Step 5 Go to Step 9
Check for
improper fuel
Go to Step 6
Verify repair Go to Step 7
Verify repair Go to Step 8