4.15FUEL PRESSURE TEST
GENERAL
The fuel pump delivers fuel to the fuel line, to a cavity in the
induction module that supplies the fuel injectors and to the
pressure regulator, where the system pressure is controlled.
Excess fuel pressure is bypassed to the fuel tank through the
pressure regulator.
See Figure 4-56.The fuel pump fuse is located under the seat.
The fuel pump can be turned on with Digital Technician or by
applying battery voltage to the fuel pump fuse.
Improper fuel system pressure may contribute to one of the
following conditions:
• Cranks, but won't run.
• Cuts out (may feel like ignition problem).
• Hesitation, loss of power or poor fuel economy.
NOTE
Refer to the electrical diagnostic manual for further information
on the function and testing of the fuel system.
TESTING
TOOL NAMEPART NUMBER
FUEL PRESSURE GAUGEHD-41182
FUEL PRESSURE GAUGE ADAPTERHD-44061
The fuel pressure gauge (0-100 PSI) allows for fuel injector
and fuel system pressure diagnosis. A special adapter allows
the gauge to be attached to the external fuel supply line.
Avoid crimping the fuel line when installing/removing fuel
pressure gauge and adapter.
1. Remove electrical caddy cover.
To prevent spray of fuel, purge system of high-pressure
fuel before supply line is disconnected. Gasoline is
extremely flammable and highly explosive, which could
result in death or serious injury. (00275a)
2. Purge the fuel supply line of high pressure gas.
a. See Figure 4-56. Remove the fuel pump fuse from
fuse block.
b. Start the engine and allow the vehicle to run.
c. When the engine stalls, operate the starter for 3
seconds to remove any remaining fuel from the fuel
lines.
Figure 4-56. Fuel Pump Fuse
Gasoline can drain from quick-connect fitting when
removing fuel line. Gasoline is extremely flammable and
highly explosive, which could result in death or serious
injury. Wipe up spilled fuel immediately and dispose of
rags in a suitable manner. (00267a)
3. Pull up on chrome sleeve of quick-connect fitting (fitting
on left side of fuel tank) and pull down on fuel supply line
to disconnect.
NOTE
The next step requires two fuel pressure gauge adapters.
Failure to use two adapters will cause the fuel line to twist.This
may result in a broken fuel line or fuel line fitting.
4. Attach fuel line to gauge assembly.
a. See Figure 4-57. Install a second adapter in series
with the first.
b. See Figure 4-58. Pull up on chrome sleeve of quick-
connect fitting and insert neck of FUEL PRESSURE
GAUGE ADAPTER (Part No. HD-44061) into fuel
supply line.
c. While pushing up on bottom of adapter, pull down on
chrome sleeve until it "clicks" into the locked position.
Tug on adapter to be sure that it will not come free.
d. In the same manner, install neck of second fuel supply
line fitting into quick-connect fitting on fuel tank. Tug
on fuel supply line to be sure that it will not come free.
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