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5B.16
Section 5B
EFI Fuel System
Figure 5B-21. Injector Inspection Points.
1. Engine must be cool. Depressurize fuel system
through test valve in fuel rail.
2. Disconnect spark plug leads from spark plugs.
3. Remove the air cleaner outer cover, inner wing
nut, element cover and air cleaner element/
precleaner. Service air cleaner components as
required.
4. Remove the two screws securing the air cleaner
base to throttle body manifold. Remove the air
cleaner base to permit access to the injectors.
Check condition of air cleaner base gasket,
replace if necessary.
5. Remove the flywheel screen if it overlaps the
blower housing.
6. If the engine has a radiator-type oil cooler
mounted to the blower housing, remove the two
oil cooler mounting screws.
7. Remove the blower housing mounting screws.
Note the location of the plated (silver) screw
attaching the rectifier-regulator ground lead.
Remove the blower housing.
Figure 5B-20. Volt Test Light.
2. Make sure all safety switch requirements are met.
Crank the engine and check for flashing of test
light. Repeat test at other connector.
a. If flashing occurs, use an ohmmeter (Rx1
scale) and check the resistance of each
injector across the two terminals. Proper
resistance is 12-20
ΩΩ
ΩΩ
Ω. If injector resistance is
correct, check whether the connector and
injector terminals are making a good
connection. If the resistance is not correct,
replace the injector following steps 1-8 and
13-16 below.
b. If no flashing occurs, reattach connectors to
both injectors. Disconnect the main harness
connector from the ECU and the connector
from the relay. Set the ohmmeter to the Rx1
scale and check the injector circuit resistance
as follows:
“35 Pin” (MA 1.7) Metal-Cased ECU: Check
the resistance between the relay terminal #87
and pin #35 in main connector. Resistance
should be 4-15
ΩΩ
ΩΩ
Ω.
“24 Pin” (MSE 1.0) Plastic-Cased ECU:
Check the resistance between relay terminal
#87 and pin #16 in main connector. Then
check resistance between relay terminal #87
and pin #17. Resistance should be 4-15
ΩΩ
ΩΩ
Ω for
each circuit.
“32 Pin” (MSE 1.1) Plastic-Cased ECU:
Check the resistance between relay terminal
#87 and pin #14 in the main connector. Then
check the resistance between relay terminal
#87 and pin #15. Resistance should be 4-15
ΩΩ
ΩΩ
Ω
for each circuit.
Check all electrical connections, connectors, and
wiring harness leads if resistance is incorrect.
Injector leakage is very unlikely, but in those rare
instances it can be internal (past the tip of the valve
needle), or external (weeping around the injector
body). See Figure 5B-21. The loss of system pressure
from the leakage can cause hot restart problems and
longer cranking times. To check for leakage it will be
necessary to remove the blower housing, which may
involve removing the engine from the unit.
Check for leaks