5B.12
Section 5B
EFI Fuel System
Figure 5B-11. Relay Connector.
a. Clean the connection and check wiring if
circuit was not completed.
3. Set the meter for DC voltage. Touch the red tester
lead to the #30 terminal in relay connector. A
reading of 12 volts should be indicated at all
times.
4. Connect the red lead of meter to the #85 terminal
in the relay connector. Turn the key switch to the
“on” position. Battery voltage should be present.
a. No voltage present indicates a problem in the
wiring or at the connector.
b. If voltage is present, the wiring to the
connector is good. Turn ignition switch ‘‘off’’
and proceed to test 5 to test the relay.
Figure 5B-12. Relay Terminal Details.
Figure 5B-13. Fuel Injector.
General
The fuel injectors mount into the intake manifold, and
the fuel rail attaches to them at the top end.
Replaceable O-Rings on both ends of the injector
prevent external fuel leakage and also insulate it from
heat and vibration. A special clip connects each injector
to the fuel rail, retaining it in place.
When the key switch is on and the relay is closed, the
fuel rail is pressurized, and voltage is present at the
injector. At the proper instant, the ECU completes the
ground circuit, energizing the injector. The valve needle
in the injector is opened electromagnetically, and the
pressure in the fuel rail forces fuel down through the
inside. The “director plate” at the tip of the injector (see
inset) contains a series of calibrated openings which
directs the fuel into the manifold in a cone-shaped
spray pattern.
Terminal #87 -
Feed To Ignition
Coils, Fuel
Injectors, and Fuel
Pump
Terminal #86 -
ECU Controlled
Ground
Terminal #87A -
Not used
Terminal #85 -
Ignition Switch
Voltage
Terminal #30 -
Permanent Battery Voltage
Terminal #85 -
Ignition Switch
Voltage
Terminal #87 -
Feed To
Ignition Coils,
Fuel Injectors,
and Fuel Pump
Terminal #86 -
ECU Controlled
Ground
Terminal #30 -
Permanent Battery Voltage
Terminal
#87A -
Not used
5. Connect an ohmmeter (Rx1 scale) between the
#85 and #86 terminals in the relay. There should
be continuity.
6. Attach ohmmeter leads to the #30 and #87
terminals in relay. Initially, there should be no
continuity. Using a 12 volt power supply, connect
the positive (+) lead to the #85 terminal and touch
the negative (-) lead to the #86 terminal. When 12
volts is applied, the relay should activate and
continuity should exist (circuit made) between the
#30 and #87 terminals. Repeat the test several
times. If, at any time the relay fails to activate the
circuit, replace the relay.
Fuel Injectors
Not For Resale
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