Mazda CX-7 2007 Workshop Manual page 363

SYMPTOM TROUBLESHOOTING [L3 WITH TC]
STEP INSPECTION
3 Remove the parts necessary to inspect
turbocharger without removing the turbocharger.
Visually inspect for the turbocharger compressor
housing.
Is any engine oil found inside turbocharger
compressor housing?
4 Inspect for the following engine internal parts.
• Damaged valve guide, stems or valve seals
• Blocked oil drain passage in cylinder head
• Piston ring is not seated, seized or worn
• Damage cylinder bore
Are there ant problem found?
5 Does cooling system hold the coolant pressure?
(See01-12-6 ENGINE COOLANT LEAKAGE
INSPECTION[L3 WITH TC].)
6 Inspect for the following for intake-air system.
• Air cleaner restriction
• Collapsed or restricted
• Leakage
Are all items normal?
7 Connect the M-MDS to the DLC-2.
Access following PIDs.
• ECT
• MAF
• IAT
• IAT2
• APP
• TP
• MAP
• VSS
• O2S11
• O2S12
• LONGFT1
• SHTFT1
Monitor the PIDs under the black smoke
appeared engine condition.
Do all PID indicate normal according to engine
conditions?
8 Inspect the wastegate.
(See01-13-16 WASTEGATE ACTUATOR
INSPECTION[L3 WITH TC].)
Does the wastegate stuck open?
RESULTS
Yes Install all parts removed in this step.
Perform the following, according to inspection
results. Excessive amount of oil is found:
Replace the turbocharger.
Small amount of oil is found:
Wipe oil out of vehicle, then Go to the next step.
No Turbocharger is normal.
Install all parts removed in this step.
Then, Go to the next step.
Yes Repair or replace suspected parts, according to the
inspection results.
No Engine internal parts are normal.
If other driveability symptoms are present, return to
diagnostic index to service additional symptoms.
Yes Inspect for the following:
• Cylinder head gasket leakage
• Intake manifold gasket leakage
• Cracked or porous engine block
If other driveability symptoms are present, return to
diagnostic index to service additional symptoms.
No Inspect for the cause.
Yes Go to the next step.
No Repair or replace the suspected part.
Yes Go to the next step.
No Inspect and repair or replace suspected parts and the
the related harnesses.
If the malfunction remains, perform the intermittent
concern troubleshooting procedure.
(See01-03-76 INTERMITTENT CONCERN
TROUBLESHOOTING[L3 WITH TC].)
Yes Perform the wastegate control system operation
inspection.
(See01-03-78 ENGINE CONTROL SYSTEM
OPERATION INSPECTION[L3 WITH TC].)
Repair or replace malfunctioning part according to the
inspection results.
No Go to the next step.
ACTION
01-03–63
01-03