Diagnostic Procedure

WARNING: This page is about a different variant/trim than selected.

STEP	INSPECTION	RESULTS	ACTION
1	VERIFY EXHAUST GAS COLOR What color is smoke coming from the exhaust system?	Blue	Burning oil is indicated. Go to the next step.
		White	Water in 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 NOTE: The PCV valve cannot be reassembled once it is removed because the tabs will have been broken. Inspect the PCV valve without removing it from the vehicle. Inspect the PCV valve with it installed. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION .) Is there any malfunction?	Yes	Replace the PCV valve. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION .)
2		No	Inspect for the following: Damaged valve guide, stems or valve seals Blocked oil drain passage in cylinder head Piston ring is not seated, seized or worn. Damaged cylinder bore If other driveability symptoms are present, return to diagnostic index to service any additional symptoms.
3	INSPECT COOLING SYSTEM FOR LEAKAGE WARNING: Never remove the cooling system cap or loosen the radiator drain plug while the engine is running, or when the engine and radiator are hot. Scalding engine coolant and steam may shoot out and cause serious injury. It may also damage the engine and cooling system. Turn off the engine and wait until it is cool. Even then, be very careful when removing the cap. Wrap a thick cloth around it and slowly turn it counterclockwise to the first stop. Step back while the pressure escapes. When you are sure all the pressure is gone, press down on the cap using the cloth, turn it, and remove it. Does the cooling system hold pressure?	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 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 for the following: Air cleaner restriction Collapsed or restricted intake-air system Restricted fuel return line Are all items normal?	Yes	Go to the next step.
4		No	Repair or replace the malfunctioning part according to the inspection results. Repeat Step 4.
5	VERIFY PCM DTC Switch the ignition to ON (Engine off). Retrieve any DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .) Are there any DTCs displayed?	Yes	DTC is displayed: Go to the appropriate DTC inspection. (See DTC TABLE .)
5		No	No DTC is displayed: 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 PCM PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST .) APP1 APP2 ECT IAT MAF MAP O2S11 O2S21 O2S12 O2S22 TP1 TP2 VSS Do the PIDs indicate the correct values under trouble condition? (See PCM INSPECTION .)	Yes	Go to the next step.
6		No	APP1 or APP2 PID is not specified: Inspect if output signal from APP sensor changes smoothly. ECT PID is not specified: Inspect intermittent short circuit of CHT sensor and related wiring harnesses. IAT PID is not specified: Inspect for air suction in intake-air system. If normal, inspect intermittent short circuit of IAT sensor and related wiring harnesses. MAF PID is not specified: Inspect for intermittent open circuit of MAF sensor and related wiring harness. MAP PID is not specified: Inspect for intermittent open circuit of MAP sensor and related wiring harness. O2S11 or O2S21 PID is not specified: Inspect for intermittent open circuit of suspect A/F sensor and related wiring harness. O2S12 or O2S22 PID is not specified: Inspect for intermittent open circuit of suspect HO2S and related wiring harness. TP1 or TP2 PID is not specified: Inspect if output signal from TP sensor changes smoothly. VSS PID is not specified: Inspect for open circuit of VSS and related wiring harness intermittently. Repair or replace the malfunctioning part according to the inspection results.
7	INSPECT FUEL LINE PRESSURE Install the fuel pressure gauge between the fuel pipe and fuel distributor. Start the engine and idle it. Measure the fuel line pressure during idle. (See FUEL LINE PRESSURE INSPECTION .) Is the fuel line pressure correct during idle?	Yes	Go to the next step.
7		No	Zero or low: Inspect for the following: Fuel pump relay Fuel pump circuit Fuel line for clogging If there is no malfunction, replace the fuel pump unit. (Fuel pump or pressure regulator malfunction) (See FUEL PUMP UNIT REMOVAL/INSTALLATION .) High: Replace the fuel pump unit. (Pressure regulator malfunction) (See FUEL PUMP UNIT REMOVAL/INSTALLATION .)
8	INSPECT IGNITION SYSTEM OPERATION Perform the spark test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION .) Is 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 Is the engine compression correct?	Yes	Inspect the fuel injector. (See FUEL INJECTOR INSPECTION .) Repair or replace the malfunctioning part according to the inspection results.
10		No	Inspect for cause. Repair or replace the malfunctioning part according to the inspection results.
11	Verify test results. If normal, return to diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX .) If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis. If vehicle is repaired, troubleshooting completed. If vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.