Mazda CX-7 2007 Workshop Manual page 124

STEP
5 VERIFY CURRENT INPUT SIGNAL STATUS
• Warm up the engine.
• Access the O2S11 PID using the M-MDS.
• Inspect the PID under the following accelerator
pedal conditions in NEUTRAL.
• Is the PID normal?
— Less than 1mA when the accelerator pedal
is suddenly depressed (rich condition).
— More than 1mA just after accelerator pedal
is released (lean condition).
6 INSPECT INSTALLATION OF FRONT HO2S
• Inspect if the front HO2S is loosely installed.
• Is the front HO2S installed securely?
7 INSPECT GAS LEAKAGE FROM EXHAUST
SYSTEM
• Visually inspect if any gas leakage is found
between the exhaust manifold and front HO2S.
• Is there gas leakage?
8 INSPECT FUEL PRESSURE (HIGH-SIDE)
• Access and monitor the FUEL PRES PID.
• Is the FUEL PRES PID value within the
specification?
(See01-40-6 PCM INSPECTION[L3 WITH
TC].)
9 IDENTIFY CAUSE BY FUEL PRESSURE
SENSOR OR HIGH PRESSURE FUEL PUMP
• Is the vehicle accelerate performance
normally?
10 INSPECT FUEL PRESSURE SENSOR
• Inspect the fuel pressure sensor.
(See01-40-35 FUEL PRESSURE SENSOR
INSPECTION[L3 WITH TC].)
• Is the fuel pressure sensor normal?
11 INSPECT HIGH PRESSURE FUEL PUMP
• Replace the high pressure fuel pump.
• Monitor FUEL_PRES PID.
• Is the FUEL_PRES PID value within the
specified?
(See01-40-6 PCM INSPECTION[L3 WITH
TC].)
12 INSPECT FUEL PRESSURE (LOW-SIDE)
• Connect the fuel pressure gauge between fuel
pump and high pressure fuel pump.
• Measure the low side fuel pressure.
(See01-40-35 FUEL PRESSURE SENSOR
INSPECTION[L3 WITH TC].)
• Is the low side fuel pressure within the
specification?
13 INSPECT SEALING OF ENGINE COOLANT
PASSAGE
• Perform the "ENGINE COOLANT LEAKAGE
INSPECTION".
(See01-12-6 ENGINE COOLANT LEAKAGE
INSPECTION[L3 WITH TC].)
• Is there any malfunction?
01-02–82
ON-BOARD DIAGNOSTIC [L3 WITH TC]
INSPECTION
Yes Go to Step 8.
No Go to the next step.
Yes Go to the next step.
No Retighten the front HO2S, then go to Step 14.
Yes Repair or replace the malfunctioning exhaust part, then go
to Step 14.
No Replace sensor, then go to Step 14.
Yes Go to Step 13.
No Go to the next step.
Yes Go to the next step.
No Go to Step 11.
Yes Go to the next step.
No Replace the fuel delivery pipe, then go to Step 14.
Yes Retest Step 14.
No Go to the next step.
Yes Go to the next step.
No Inspect for the following:
• Fuel line restriction
• Fuel filter clogging
If normal replace the fuel pump. Then go to Step 14.
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the
inspection results.
Then go to the next step.
ACTION