Dodge ram truck 3500 1996 Service Manual page 1242

14 - 8 FUEL SYSTEM
BR
DIAGNOSIS AND TESTING (Continued)
(11) After performing pressure test, install fuel
line into fuel rail. Install latch clip into fuel rail.
Refer to Quick-Connect Fittings for procedures. This
can be found in this section of the group.
FUEL GAUGE SENDING UNIT
For fuel gauge diagnosis, refer to Group 8E,
Instrument Panel and Gauges.
FUEL
INJECTORS
To perform a complete test of the fuel injectors and
their circuitry, refer to DRB scan tool and appropri­
ate Powertrain Diagnostics Procedures manual. To
test the injector only, refer to the following:
Disconnect the fuel injector wire harness connector
from the injector (Fig. 9). Place an ohmmeter across
the injector terminals. Resistance reading should be
approximately 14.5 ohms ±1.2 ohms at 20°C (68°F).
Proceed to following Injector Diagnosis chart. When
performing the following tests from the chart,
do not leave electrical current applied to the
injector for longer than five seconds. Damage
to injector coil or internal injector seals (Fig.
10) could result.
FUEL
INJECTOR J9214-30
Fig. 9 Fuel Injector Wiring Connector—Typical
S E R V I C E P R O C E D U R E S
FUEL SYSTEM PRESSURE RELEASE
PROCEDURE-WITH PRESSURE TEST PORT
NOTE: The fuel pressure test port Is used on cer­
tain engines only. If equipped, the test port will be
located on the fuel rail near the throttle position
SPACER J9414-58
Fig. 10 Fuel Injector Internal Components—Typical
sensor (Fig. 7 ) . A sealing cap is screwed onto the
test port.
The fuel system is under constant fuel pressure
(even with the engine off).
WARNING: BECAUSE THE FUEL SYSTEM IS
UNDER CONSTANT FUEL PRESSURE, THE PRES­
SURE MUST BE RELEASED BEFORE SERVICING
ANY FUEL SYSTEM COMPONENT. THIS DOES NOT
APPLY TO THROTTLE BODY REMOVAL.
(1) Disconnect negative battery cable.
(2) Remove the fuel tank filler tube cap to release
fuel tank pressure.
(3) Remove protective cap from pressure test port
on the fuel rail. This is located on top of fuel rail
near the throttle position sensor.
WARNING:' DO NOT ALLOW FUEL TO SPILL ONTO
THE ENGINE INTAKE OR EXHAUST MANIFOLDS.
PLACE SHOP TOWELS UNDER AND AROUND THE
PRESSURE PORT TO ABSORB FUEL WHEN THE
PRESSURE IS RELEASED FROM THE FUEL RAIL.
WARNING: WEAR PROPER EYE PROTECTION
WHEN RELEASING FUEL SYSTEM PRESSURE.
(4) Obtain the fuel pressure gauge/hose assembly
from fuel pressure gauge tool set 5069. Remove the
gauge from the hose.
(5) Place one end of hose (gauge end) into an
approved gasoline container.
(6) Place a shop towel under the test port.
(7) To release fuel pressure, screw the other end of
hose onto the fuel pressure test port.
(8) After fuel pressure has been released, remove
the hose from the test port.
(9) Install protective cap to fuel test port.