Jeep 1987 Wrangler Workshop Manual page 1525

m
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THROTTLE BODY FUEL INJECTION SYSTEM
#11G
m
G
1.4L 1983-1985
#11G
TROUBLE
CODE/CONDITION POSSIBLE CAUSE CORRECTION
Engine wil! not start.
Defective WOT switch.
Low battery voltage.
Fuel supply too low.
Low fuel pressure.
Fuel pump inoperative.
Defective secondary ignition
circuit.
Primary ignition input to the
ECU defective.
No battery voltage applied to the
injector (12V from one pin to
chasis ground).
Injector resistance too high
(ohmmeter should indicate less
than 10 ohms).
ECU is not switching the
injector.
Leaking injector.
If the pressure drops, replace
the fuel return pipe. Inspect the
fuel tank fittings and replace if
restricted. If the pressure does
not drop, install a fuel pressure
regulator kit.
Refer to the WOT switch test
procedure.
Replace or charge the battery.
Replinish as necessary.
Refer to the fuel pressure test.
Correct as necessary. Replace
the fuel filter.
Repair or replace as necessary.
Position a spark plug (with
ignition wire) on the cylinder
block. Engage the starter motor
and observe the spark.
Repair or replace the ignition
module or wiring.
Connect a voltmeter between D1
Pin 2 and ground. With key on
(engine stopped) voltage should be
close to battery voltage.
Check the harness and
connectors between the E C U
and the ignition module. Service
the ignition module as
necessary.
Check the B + relay. Check the
wire harness and connectors.
Repair or replace as necessary.
Replace the injector.
Remove the injector wire
harness connector. Connect a
test lamp across the connector.
Engage the starter motor. The
lamp should pulse dimly.
Check the E C U with MS 1700
tester.
Check to determine if the
injector is discharging fuel when
the engine is rotated by the
starter motor.
Install an O-ring kit if it is
leaking fuel. Replace the
injector if it either discharges no
fuel with engine turning or drips
fuel with the engine stopped.
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