5B.14
Section 5B
EFI Fuel System
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
Ω
Ω
Ω
Ω
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: 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
Ω
Ω
Ω
Ω
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-17. 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
1. Engine must be cool. Depressurize fuel system
through the test valve in fuel rail.
2. Disconnect the spark plug leads from spark plugs.
3. Remove the air cleaner outer cover, inner wing nut,
element cover and air cleaner element/precleaner.
Service the 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.
8. Thoroughly clean the area around and including the
throttle body/manifold and the injectors.
9. Disconnect the throttle linkage and damper spring
from the throttle lever. Disconnect the TPS lead
from the harness.
10. Remove the manifold mounting bolts and separate
the throttle body/manifold from the engine leaving
the TPS, fuel rail, air baffle, injectors and line
connections intact. Discard the old gaskets.
11. Position the manifold assembly over an appropriate
container and turn the key switch “on” to activate
the fuel pump and pressurize the system. Do not
turn switch to “start” position.
12. If either injector exhibits leakage of more than two
to four drops per minute from the tip, or shows any
sign of leakage around the outer shell, turn the
ignition switch off and replace injector as follows.
13. Depressurize the fuel system following the
procedure in the fuel warning on page 5B.2.
Remove the two fuel rail mounting screws.
Figure 5B-17. Injector Inspection Points.
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