Exhaust System Concerns

EXHAUST SYSTEM CONCERNS DESCRIPTION

16
DESCRIPTION	Smoke

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	IDENTIFY EXHAUST SMOKE COLOR Identify the color of the exhaust smoke. Is the exhaust smoke either black, blue or white?	Yes	For black smoke: Rich fuel mixture indicated. Go to next step. For blue smoke: Burning oil indicated. Go to step 8. White smoke: Water in combustion indicated. Go to step 7.
1		No	Attempt to verify symptom and exhaust smoke color.
2	BLACK SMOKE: PRELIMINARY CHECKS Perform the following preliminary checks: Air cleaner (restricted airflow). Air tube (collapsed, restricted). Fuel return lines (restricted). Are all checks OK?	Yes	Go to next step.
2		No	Service as required. Verify symptom no longer exists.
3	PERFORM PCM QUICK TEST See PCM QUICK TEST . Are any DTCs displayed during Continuous Memory or Key ON, Engine OFF (KOEO), Engine OFF (KOEO) Self-Tests?	Yes	Check for cause. See DIAGNOSTIC TROUBLE CODE (DTC) INDEX - POWERTRAIN CONTROL MODULE (PCM) .
3		No	Go to next step.
4	CHECK FUEL DELIVERY SYSTEM Perform fuel pressure inspection. See TEST 9: FUEL LINE/FUEL PRESSURE HOLD INSPECTION . Fuel line pressure: 240 - 380 kPa (35 - 55 psi) Is fuel pressure correct?	Yes	Go to next step.
4		No	If pressure is greater than 380 kPa (55 psi): Replace fuel pump. See FUEL PUMP MODULE . If pressure is less than 240 kPa (35 psi): Check fuel supply line for restriction.
5	CHECK FUEL DELIVERY SYSTEM Check fuel pump fuel flow. See TEST 4: FUEL DELIVERY SYSTEM . Did fuel system flow the required amount of fuel?	Yes	Check injector for leakage. See TEST 10: FUEL INJECTOR INSPECTION . If injector leaks, service as necessary. See FUEL INJECTORS . If injector OK, go to next step.
5		No	Check fuel supply line for restriction.
6	CHECK SECONDARY IGNITION SYSTEM Is strong blue spark visible at each disconnected high-tension lead while cranking engine?	Yes	Check spark plugs: If OK, Go to next step. If not OK, clean or replace spark plugs. See IGNITION COIL-ON-PLUG AND SPARK PLUG - 2.3L or IGNITION COIL-ON-PLUG AND SPARK PLUG - 3.0L (4V) .
6		No	Check following: High-tension leads. See TEST 15: IGNITION SCOPE TEST . CKP sensor. See CRANKSHAFT POSITION (CKP) SENSOR MALFUNCTION . See CAMSHAFT POSITION SENSOR (CMP) MALFUNCTION .
7	WHITE SMOKE: CHECK BASE ENGINE/COOLING SYSTEM Check for base engine concerns (such cylinder head gasket leaks, intake manifold gasket leaks, engine block cracked or porous). See ENGINE . Also, check for loss of coolant. See SYMPTOM TROUBLESHOOTING CHART - ENGINE COOLING SYSTEM . Is a fault indicated?	Yes	Service as required.
7		No	For 2.3L engine, Go to next step. For 3.0L engine, Go to Step 9.
8	BLUE SMOKE: CHECK PCV SYSTEM Remove PCV valve and shake it. Does PCV valve rattle?	Yes	Install PCV valve. Go to next step.
8		No	Replace PCV valve. See POSITIVE CRANKCASE VENTILATION (PCV) VALVE - 2.3L .
9	CHECK BASE ENGINE Start engine and bring to normal operating temperature. Disconnect crankcase ventilation hose from throttle body. Place a stiff piece of paper over the hose. Wait one minute. Does vacuum hold paper in place?	Yes	Go to next step.
9		No	Disconnect evaporative hose. Place a stiff piece of paper over the hose. Wait one minute. Does vacuum hold paper in place? If yes, See EVAPORATIVE EMISSION (EVAP) MONITOR AND SYSTEM MALFUNCTION . If no, check for vacuum leaks, obstructions in the PCV system, oil cap, PCV valve, valve cover bolt torque/gasket leak. Service as required.
10	CHECK BASE ENGINE Check for base engine concerns (such as damaged valve guides, valve stems, valve seals, blocked oil drain passages in the heads (blue smoke on start-up) piston rings (not seated, seized, worn) damaged cylinder bores). See ENGINE . Is a fault indicated?	Yes	Service as required.
10		No	Go to next step.
11	Verify test results. If OK, See DIAGNOSTIC INDEX to service any additional symptoms.