Remove the air duct from throttle valve body.
Verify that the throttle valve opens when throttle pedal is depressed.
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If the throttle valve opens, inspect the throttle position sensor and related wiring
harness.
z
If the throttle valve does not open, inspect the throttle actuator control motor and
related wiring harness.
FUEL INJECTOR OPERATION INSPECTION
FUEL INJECTOR OPERATION INSPECTION CHART
FUEL CUT CONTROL SYSTEM INSPECTION
If simulation function of the M-MDS is used:
1. Warm up the engine and idle it.
2. Connect the M-MDS to the DLC-2.
3. Select the RPM and FUELSYS1 PIDs.
STEP
INSPECTION
RESULTS
ACTION
1
While cranking the engine, inspect for fuel
injector operation sound at each cylinder using a
soundscope.
Is operation sound heard?
Yes
Fuel injector operation is normal.
No
All cylinders not heard:
Go to the next step.
Some cylinders not heard:
Go to Step 3.
2
Perform main relay operation inspection.
Is main relay operation normal?
Yes
Inspect the following:
z
Fuel injector power system
related wiring harness and
connectors
z
PCM connectors
z
Fuel injector GND and related
wiring harness and connectors
No
Repair or replace malfunctioning
parts.
3
Switch fuel injector connector of not operating
fuel injector with operating fuel injector.
Is operation sound heard?
Yes
Go to the next step.
No
Replace the fuel injector.
4
Are wiring harness and connectors of not
operation fuel injector normal? (Open or short)
Yes
Inspect PCM terminal voltage of fuel
injector signal.
No
Repair or replace malfunctioning
parts.
NOTE:
z
This inspection has to perform after the Fuel Injector Operation Inspection.
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:10:06 AM
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