Symptom Chart - Engine Performance

WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART - ENGINE PERFORMANCE

Condition	Possible Sources	Action
Difficult starting	Inoperative or damaged glow plug system Inoperative or damaged fuel system Inoperative or damaged starting system	INSPECT each system for damage. Refer to the appropriate article for the procedure. REFER to the INTRODUCTION - DIESEL MODELS . REPAIR as necessary. TEST the system for normal operation.
	Damaged charging system/battery	REFER to CHARGING SYSTEM .
	Burnt valve	INSPECT the valve(s) and valve seat(s) for damage. REFER to VALVE INSPECTION and VALVE SEAT INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn piston	INSPECT the piston(s) for wear. REFER to PISTON INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn piston ring(s)	INSPECT the piston ring(s) for wear. REFER to PISTON RING END GAP and PISTON INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn cylinder	INSPECT the cylinder bore for wear. REFER to CYLINDER BORE OUT-OF-ROUND . REPAIR as necessary. TEST the system for normal operation.
	Damaged head gasket	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the head gasket(s). REPAIR as necessary. TEST the system for normal operation.
Poor idling	Inoperative or damaged cooling system	INSPECT the cooling system for damage. REFER to ENGINE COOLING - DIESEL ENGINES . REPAIR as necessary. TEST the system for normal operation.
	Inoperative or damaged fuel system	INSPECT the fuel system for damage. REFER to the INTRODUCTION - DIESEL MODELS . REFER to FUEL CHARGING AND CONTROLS - 6.7L DIESEL . REPAIR as necessary. TEST the system for normal operation.
	Damaged hydraulic lash adjuster	INSPECT the hydraulic lash adjuster(s) for damage. REFER to HYDRAULIC LASH ADJUSTER INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Incorrect valve-to-seat contact	INSPECT the valve(s) and valve seat(s) for damage. REFER to VALVE INSPECTION and VALVE SEAT INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Damaged head gasket(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the head gasket(s). REPAIR as necessary. TEST the system for normal operation.
Abnormal combustion	Inoperative or damaged fuel system Leaking or damaged Charge Air Cooler (CAC), upper intake or gaskets EGR system fault Inoperative or damaged cooling system	INSPECT each system for damage. Refer to the appropriate article for the procedure. REFER to the INTRODUCTION - DIESEL MODELS . REPAIR as necessary. TEST the system for normal operation.
	Malfunctioning or damaged air intake system	INSPECT the air intake system for damage. REFER to INTAKE AIR DISTRIBUTION & FILTERING . Repair as necessary. TEST the system for normal operation.
	Damaged hydraulic lash adjuster(s)	INSPECT the hydraulic lash adjuster(s) for damage. REFER to HYDRAULIC LASH ADJUSTER INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Burnt or sticking valve	INSPECT the valve(s) and valve seat(s) for damage. REFER to VALVE INSPECTION and VALVE SEAT INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn valve guides, valves and seals	INSPECT the valve(s) and valve guide(s) for wear. REFER to VALVE INSPECTION and VALVE GUIDE INNER DIAMETER . REPAIR as necessary. TEST the system for normal operation.
	Weak or broken valve spring(s)	INSPECT the valve spring(s) for damage. REFER to VALVE SPRING FREE LENGTH . REPAIR as necessary. TEST the system for normal operation.
	Turbocharger shaft seals	REMOVE and INSPECT the Turbocharger. REFER to FUEL CHARGING AND CONTROLS - TURBOCHARGER . REPAIR as necessary. TEST the system for normal operation.
Excessive oil consumption	Leaking oil	REPAIR oil leakage.
	Oil dilution (fuel)	INSPECT the fuel injectors. REFER to FUEL CHARGING AND CONTROLS - 6.7L DIESEL . REPAIR as necessary. TEST the system for normal operation.
	Malfunctioning crankcase vent oil separator	INSPECT the crankcase vent oil separator for damage. REFER to ENGINE EMISSION CONTROL . REPAIR as necessary. TEST the system for normal operation.
	Worn valve stem seal	INSPECT the valve(s) and valve stem seal(s) for wear. REFER to VALVE INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn valve stem or valve guide	INSPECT the valve(s) and valve guide(s) for wear. REFER to VALVE INSPECTION and VALVE GUIDE INNER DIAMETER . REPAIR as necessary. TEST the system for normal operation.
	Sticking piston rings	INSPECT the piston(s) and cylinder block for wear. REFER to PISTON INSPECTION and CYLINDER BORE OUT-OF-ROUND . REPAIR as necessary. TEST the system for normal operation.
	Worn piston ring groove	INSPECT the piston(s) for wear. REFER to PISTON INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn piston or cylinder	INSPECT the piston(s) and cylinder block for wear. REFER to PISTON INSPECTION and CYLINDER BORE OUT-OF-ROUND . REPAIR as necessary. TEST the system for normal operation.
	Turbocharger shaft seals	REMOVE and INSPECT the turbocharger. REFER to FUEL CHARGING AND CONTROLS - TURBOCHARGER . REPAIR as necessary. TEST the system for normal operation.
Insufficient power	Inoperative or damaged fuel system	REFER to the INTRODUCTION - DIESEL MODELS .
	Oil level too high	DRAIN oil to correct level.
	Incorrect engine oil	INSTALL correct specification engine oil.
	Low oil pressure	CARRY OUT the OIL PRESSURE TEST . If not within specifications, GO to the LOW OIL PRESSURE TEST . REPAIR as necessary. TEST the system for normal operation.
	Excessive accessory drive belt loading	INSPECT the accessory drive system for damage. REFER to ACCESSORY DRIVE . REPAIR as necessary. TEST the system for normal operation.
	Inoperative or damaged cooling system	INSPECT the cooling system for damage. REFER to ENGINE COOLING - DIESEL ENGINES . REPAIR as necessary. TEST the system for normal operation.
	Damaged or plugged exhaust system	INSPECT the exhaust system for flow and damage. REFER to EXHAUST SYSTEM . REPAIR as necessary. TEST the system for normal operation.
	Incorrect tire size	REFER to SUSPENSION SYSTEM - GENERAL INFORMATION .
	Dragging brakes	REFER to BRAKE SYSTEM - GENERAL INFORMATION .
	Slipping transmission	REFER to AUTOMATIC TRANSAXLE/TRANSMISSION - TORQSHIFT 6 .
	Malfunctioning hydraulic lash adjuster	INSPECT the hydraulic lash adjuster for wear or damage. REFER to HYDRAULIC LASH ADJUSTER INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Compression leakage at valve seat	INSPECT the valve(s) and valve seat(s) for wear. REFER to VALVE INSPECTION and VALVE SEAT INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Seized valve stem	INSPECT the valve for wear or damage. REFER to VALVE INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Weak or broken valve spring	INSPECT the valve spring. REFER to VALVE SPRING FREE LENGTH . REPAIR as necessary. TEST the system for normal operation.
	Worn or damaged camshaft	INSPECT the camshaft for wear or damage. REFER to CAMSHAFT LOBE LIFT . REPAIR as necessary. TEST the system for normal operation.
	Damaged head gasket(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the head gasket(s). REPAIR as necessary. TEST the system for normal operation.
	Cracked or distorted cylinder head(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the cylinder head(s). REPAIR as necessary. TEST the system for normal operation.
	Damaged, worn or sticking piston ring(s)	INSPECT the piston(s) and cylinder block for wear. REFER to PISTON INSPECTION and CYLINDER BORE OUT-OF-ROUND . REPAIR as necessary. TEST the system for normal operation.
	Worn or damaged piston	INSPECT the piston for damage. REFER to PISTON INSPECTION . REPAIR as necessary. TEST the system for normal operation.
	Worn or damaged cylinder	INSPECT the cylinder for damage. REFER to CYLINDER BORE OUT-OF-ROUND . REPAIR as necessary. TEST the system for normal operation.
	Boost leaks or blockage	CHECK the air intake ducts, Air Cleaner (ACL), CAC pipes and CAC for leaks and correct fit. REFER to INTAKE AIR DISTRIBUTION & FILTERING . REPAIR as necessary. TEST the system for normal operation.
	Damaged turbocharger	REMOVE and INSPECT the turbocharger. REFER to FUEL CHARGING AND CONTROLS - TURBOCHARGER . REPAIR as necessary. TEST the system for normal operation.
Low oil pressure	Inaccurate gauge reading	DIAGNOSE the Instrument Panel Cluster (IPC). REFER to INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES .
	Low oil level	ADJUST the oil level.
	Oil dilution (fuel)	INSPECT the fuel injectors. REFER to FUEL CHARGING AND CONTROLS - 6.7L DIESEL . REPAIR as necessary. TEST the system for normal operation.
	Stuck open oil pressure regulator	INSTALL a new engine front cover. REFER to ENGINE FRONT COVER . TEST the system for normal operation.
	Scored/damaged oil pump	INSTALL a new engine front cover. REFER to ENGINE FRONT COVER . TEST the system for normal operation.
	Broken or damaged piston cooling tubes	REMOVE the upper oil pan. REFER to OIL PAN - UPPER . INSPECT the piston cooling tubes. REPAIR as necessary. TEST the system for normal operation.
	Front cover gasket leaks	REMOVE the engine front cover. REFER to ENGINE FRONT COVER . INSPECT the gasket. REPAIR as necessary. TEST the system for normal operation.
	Leaking/missing core plugs	INSPECT for leaking/missing core plugs. REFER to CORE PLUG REPLACEMENT . REPAIR as necessary. TEST the system for normal operation.
	Worn/damaged/missing bearing shell(s)	CHECK the crankshaft main bearings and connecting rod bearings. CARRY OUT the CRANKSHAFT MAIN BEARING JOURNAL-TO-BEARING CLEARANCE and CONNECTING ROD BEARING JOURNAL-TO-BEARING CLEARANCE procedure. REPAIR as necessary. TEST the system for normal operation.
	Restriction in the pickup tube or oil pan	REMOVE the upper oil pan. REFER to OIL PAN - UPPER . INSPECT the oil pan and pickup tube. REPAIR as necessary. TEST the system for normal operation.
	External oil leaks	INSPECT the engine for oil leaks. REPAIR as necessary. TEST the system for normal operation.
Oil in coolant	Damaged head gasket(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the head gasket(s). REPAIR as necessary. TEST the system for normal operation.
	Leaking oil cooler	REMOVE the oil cooler. REFER to OIL COOLER . INSPECT the oil cooler. REPAIR as necessary. TEST the system for normal operation.
	Damaged cylinder head(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the cylinder head(s). REPAIR as necessary. TEST the system for normal operation.
Coolant in oil	Damaged head gasket(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the head gasket(s). REPAIR as necessary. TEST the system for normal operation.
	Leaking oil cooler	REMOVE the oil cooler. REFER to OIL COOLER . INSPECT the oil cooler. REPAIR as necessary. TEST the system for normal operation.
	Damaged cylinder head(s)	REMOVE the cylinder head(s). REFER to CYLINDER HEAD . INSPECT the cylinder head(s). REPAIR as necessary. TEST the system for normal operation.
	Leaking turbocharger base gasket	REMOVE the turbocharger. REFER to FUEL CHARGING AND CONTROLS - TURBOCHARGER . REPAIR as necessary. TEST the system for normal operation.
	RH valve cover or gasket	REMOVE the RH valve cover. REFER to VALVE COVER - RH . INSPECT the valve cover and gasket. REPAIR as necessary. TEST the system for normal operation.
	Engine front cover	REMOVE the engine front cover. REFER to ENGINE FRONT COVER . INSPECT the engine front cover gaskets. REPAIR as necessary. TEST the system for normal operation.
	Cracked engine block	REPLACE the engine block. REFER to Engine . REPAIR as necessary. TEST the system for normal operation.