Diagnostic Procedure

STEP	INSPECTION	RESULTS	ACTION
1	VERIFY EXHAUST GAS COLOR What color is the smoke coming from the exhaust system?	Blue	Burning oil is indicated: Go to the next step.
		White	Water in the combustion is indicated: Go to Step 3.
		Black	Rich fuel mixture is indicated: Go to Step 4.
2	INSPECT IF MALFUNCTION CAUSE IS PCV VALVE OR OTHER Inspect the PCV valve. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION .) Is there any malfunction?	Yes	Replace the PCV valve and the oil separator as a single unit, then go to the next step. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION .)
2		No	Inspect the following: Blocked oil drain passage in the cylinder head Damaged cylinder bore Damaged valve guide, stems or valve seals Piston ring is not seated, seized or worn. Repair or replace the malfunctioning part according to the inspection results. If other drivability symptoms are present: Return to the diagnostic index to service any additional symptoms.
3	INSPECT COOLING SYSTEM FOR LEAKAGE Does the cooling system hold pressure?	Yes	Inspect the following: Cracked or porous engine block Cylinder head gasket leakage Intake manifold gasket leakage If other drivability symptoms are present: Return to the diagnostic index to service any additional symptoms.
3		No	Inspect for cause. Repair or replace the malfunctioning part according to the inspection results.
4	INSPECT INTAKE AIR SYSTEM Inspect the following: Air cleaner restriction Collapsed or restricted intake air system Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Repeat Step 4.
4		No	Go to the next step.
5	VERIFY PCM DTC Perform the PCM DTC inspection using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE .)
5		No	Go to the next step.
6	VERIFY CURRENT INPUT SIGNAL STATUS CAUTION: While performing this step, always operate the vehicle in a safe and lawful manner. When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later. Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST .) APP1 APP2 ECT IAT MAF MAP O2S11 O2S12 TP1 TP2 VSS Monitor the PIDs under the black smoke appeared engine condition. Do the PIDs indicate normal according to engine conditions? (See PCM INSPECTION .)	Yes	Go to the next step.
6		No	APP1, APP2 PIDs are not as specified: Inspect if the output signal from the APP sensor changes smoothly. (See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION .) ECT PID is not as specified: Inspect for an intermittent open circuit of the ECT sensor and the related wiring harness. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION .) IAT PID is not as specified: Inspect for an intermittent open circuit of the IAT sensor and the related wiring harness. (See INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION .) MAF PID is not as specified: Inspect for an intermittent open circuit of the MAF sensor and the related wiring harness. (See MASS AIR FLOW (MAF) SENSOR INSPECTION .) MAP PID is not as specified: Inspect for an intermittent open circuit of the MAP sensor and the related wiring harness. (See MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INSPECTION .) O2S11 PID is not as specified: Inspect for an intermittent open circuit of the A/F sensor and the related wiring harness. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION .) O2S12 PID is not as specified: Inspect for an intermittent open circuit of the HO2S and the related wiring harness. (See HEATED OXYGEN SENSOR (HO2S) INSPECTION .) TP1, TP2 PIDs are not as specified: Inspect if the output signal from the TP sensor changes smoothly. (See THROTTLE POSITION (TP) SENSOR INSPECTION .) VSS PID is not as specified: Inspect for an intermittent open circuit in the VSS and related wiring harness. (See VEHICLE SPEED SENSOR (VSS) INSPECTION .) Repair or replace the malfunctioning part according to the inspection results.
7	INSPECT FUEL LINE PRESSURE Inspect the fuel line pressure. (See FUEL LINE PRESSURE INSPECTION .) Is there any malfunction?	Yes	Zero or low: Inspect the fuel pump relay and the fuel pump circuit. (See RELAY INSPECTION .) Inspect the fuel line for restriction. If there is any malfunction: Repair or replace the malfunctioning part according to the inspection results. If there is no malfunction: Replace the fuel pump unit. (Pressure regulator or fuel pump malfunction) (See FUEL PUMP UNIT REMOVAL/INSTALLATION .) High: Replace the fuel pump unit. (Pressure regulator malfunction) (See FUEL PUMP UNIT REMOVAL/INSTALLATION .)
7		No	Go to the next step.
8	INSPECT IGNITION SYSTEM OPERATION Perform the Spark Test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Is a strong blue spark visible at each cylinder?	Yes	Go to the next step.
8		No	Repair or replace the malfunctioning part according to the inspection results.
9	INSPECT CMP SENSOR Inspect the CMP sensor. (See CAMSHAFT POSITION (CMP) SENSOR INSPECTION .) Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results.
9		No	Go to the next step.
10	INSPECT ENGINE COMPRESSION Measure the compression pressure for each cylinder. (See COMPRESSION INSPECTION .) Are the compression pressures within the specification?	Yes	Inspect the fuel injector for each cylinder. (See FUEL INJECTOR INSPECTION .) Replace the suspected fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION .)
10		No	Inspect the following: Damaged valve seat Worn valve stem and valve guide Worn or stuck piston ring Worn piston, piston ring or cylinder Improper valve timing Repair or replace the malfunctioning part according to the inspection results.
11	Verify test results. If normal, return to the diagnostic index to service any additional symptoms. (See ENGINE CONTROL SYSTEM SYMPTOM DIAGNOSTIC INDEX .) If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. If the vehicle is repaired, troubleshooting is completed. If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.