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GENERAL SYSTEM DIAGNOSTICS
SERVICE MANUAL NUMBER 23
Page 5E-68
90-861326--1 MARCH 1999
Chart A-3 (3 of 5): Engine Cranks But Will Not Run
Step
Action
Value(s)
Yes
No
6
1. Disconnect one injector electri-
cal connector.
2. Connect test light J34730-2C
to injector harness connector.
3. While cranking engine, check
for blinking light.
4. Remove test light and recon-
nect injector harness connec-
tor. Repeat this test for all injec-
tors.
5. If any lights are blinking dimly,
check for shorted injector by
comparing injector resistance
values.
Were All Lights Blinking
Brightly?
–
Go to Step
7
Go to Step
10
7
1. Install fuel pressure gauge.
2. Ignition “OFF” for 10 seconds.
3. Ignition “ON.” Fuel pump will
run for about 2 seconds
4. Note fuel pressure with pump
running. The pressure may
drop after the pump stops run-
ning
Is Fuel Pressure Within
Specified Value?
34-38 psi
(234-262
kPa)
Refer to Diag-
nostic Aids on
Facing Page
Go to
Chart A-4
8
Check for secondary ignition
spark.
Is Adequate Spark Present At All
Cylinders?
_
Go to Step
9
Refer to
Ignition
System Check_
9
1. Ignition “OFF.”
2. Disconnect ECM “J2” connec-
tor.
3. Using a DVOM connected to
ground, probe “J2-8” of the
ECM harness connector while
cranking the englne.
Is The Voltage Within The
Specified Value?
1-2 volts
Go to Step
20
Go to Step
15
10
Was The Test Light A Steady
Light?
_
Go to Step
11
Go to Step
12
11
Check the injector driver circuit
with the steady light for a short to
ground. If circuit is not shorted,
check resistance across each in-
jector in the circuit.
Is Resistance Greater Than The
Specified Value?
10 Ohms
Go to Step
20
Go to Step
16
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