1. |
Release the residual pressure in fuel line
(Refer to “Release Residual Pressure in Fuel Line” in this
group).
When removing the fuel pump relay, a
Diagnostic Trouble Code (DTC) may occur. Delete the code with
the GDS after completion of “Release Residual Pressure in Fuel
Line”
work. | |
2. |
Install the Special Service Tool
(SST).
(1) |
Disconnect the fuel feed tube from the
delivery pipe.
There may be some residual
pressure even after “Release Residual Pressure in Fuel
Line” work, so cover the hose connection with a shop
towel to prevent residual fuel from spilling out before
disconnecting any fuel
connection. | |
(2) |
Install the special service tool for
measuring the fuel pressure in between the fuel feed tube and
the fuel delivery pipe (Refer to the figure
below).

| |
3. |
Inspect fuel leakage on connections among the
fuel feed tube, the delivery pipe, and the SST components with IG
ON. |
4. |
Measure Fuel Pressure.
(1) |
Start the engine and measure the fuel
pressure at idle.
Fuel Pressure: 324 ~
363 kPa (3.3 ~ 3.7 kgf/cm², 46.9 ~ 52.6
psi)
|
If the fuel pressure differs from
the standard value, repair or replace the related part
(Refer to the table
below). |
Fuel
Pressure
|
Cause
|
Related
Part
|
Too Low
|
Fuel filter clogged
|
Fuel Filter
|
Fuel leakage
|
Fuel Pressure Regulator
|
Too High
|
Fuel pressure regulator valve
stuck
|
Fuel Pressure
Regulator
|
|
(2) |
Stop the engine, and then check for the
change in the fuel pressure gauge reading.
Standard Value: The
gauge reading should hold for about 5 minutes after the
engine stops
|
If the gauge reading should not be
held, repair or replace the related part (Refer to the
table below). |
Fuel
Pressure (After Engine Stops
|
Cause
|
Related Part
|
Fuel Pressure Drops Slowly
|
Leakage on injector
|
Injector
|
Fuel Pressure Drops Immediately
|
Check valve of fuel pump stuck open
|
Fuel
Pump
|
|
(3) |
Turn the ignition switch
OFF. | |
5. |
Release the residual pressure in fuel line
(Refer to “Release Residual Pressure in Fuel Line”).
When removing the fuel pump relay, a
Diagnostic Trouble Code (DTC) may occur. Delete the code with
the GDS after completion of “Release Residual Pressure in Fuel
Line”
work. | |
6. |
Test End
(1) |
Remove the Special Service Tool (SST)
from the fuel feed tube and the delivery
pipe. |
(2) |
Connect the fuel feed tube and the
delivery
pipe. | |
Release Residual Pressure in Fuel
Line |
There may be some residual pressure even after
“Release Residual Pressure in Fuel Line” work, so cover the hose
connection with a shop towel to prevent residual fuel from spilling
out before disconnecting any fuel connection.
|
1. |
Turn the ignition switch OFF and disconnect
the battery (-) cable. |
2. |
Remove the fuel pump relay (A).

When removing the fuel pump relay, a
Diagnostic Trouble Code (DTC) may occur. Delete the code with
the GDS after completion of “Release Residual Pressure in Fuel
Line”
work. | |
3. |
Connect the battery (-)
cable. |
4. |
Start the engine and let idle, and then turn
the ignition switch OFF after the engine has stopped on its
own. |
5. |
Disconnect the battery (-) cable, and then
install the fuel pump relay (A). |
6. |
Connect the battery (-)
cable. |
7. |
Delete the Diagnostic Trouble Code (DTC)
related the fuel pump relay with the
GDS. | |