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Symptom Chart - Engine Performance

WARNING: This page is about a different car, the 2020 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
Symptom Possible Sources Action
Difficult starting Inoperative or damaged ignition system
Air or vacuum leak
Inoperative or damaged fuel system
Inoperative or damaged starting system
Inoperative or damaged VCT oil control solenoid(s)
Refer to the appropriate article for the procedure. Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Damaged charging system/ battery REFER to: Charging System - 2.7L EcoBoost (238kW/324PS)/3.5L EcoBoost (272kW/370PS) . or REFER to: Charging System - 3.3L Duratec-V6/5.0L 32V Ti-VCT .
Burnt valve INSTALL a new cylinder head. For Engine - 2.7L EcoBoost REFER to: Cylinder Head LH . For Engine - 2.7L EcoBoost REFER to: Cylinder Head RH . or For Engine - 3.3L Duratec-V6 REFER to: Cylinder Head LH . For Engine - 3.3L Duratec-V6 REFER to: Cylinder Head RH . or For Engine - 3.5L EcoBoost REFER to: Cylinder Head - Body Off - LH . For Engine - 3.5L EcoBoost REFER to: Cylinder Head - Body Off - RH . or For Engine - 5.0L 32V Ti-VCT REFER to: Cylinder Head LH . For Engine - 5.0L 32V Ti-VCT REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Worn piston INSTALL a new piston. TEST the system for normal operation after the repair.
Worn piston rings INSTALL new piston rings. TEST the system for normal operation after the repair.
Worn cylinder INSTALL a new cylinder block. TEST the system for normal operation after the repair.
Damaged head gasket INSTALL a new cylinder head gasket. Engine - 2.7L EcoBoost REFER to: Cylinder Head LH . Engine - 2.7L EcoBoost REFER to: Cylinder Head RH . or Engine - 3.3L Duratec-V6 REFER to: Cylinder Head LH . Engine - 3.3L Duratec-V6 REFER to: Cylinder Head RH . orEngine - 3.5L EcoBoost REFER to: Cylinder Head - Body Off - LH . Engine - 3.5L EcoBoost REFER to: Cylinder Head - Body Off - RH . or Engine - 5.0L 32V Ti-VCT REFER to: Cylinder Head LH . Engine - 5.0L 32V Ti-VCT REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Inoperative or damaged cooling system Refer to the appropriate article for the procedure.For 2.7L REFER to: Engine Cooling . or For 3.3L REFER to: Engine Cooling . or For 2.7L EcoBoost REFER to: Engine Cooling . or For 5.0L 32V Ti-VCT REFER to: Engine Cooling .
Fail-safe cooling invoked (if equipped) Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Poor idling Vacuum leaks
Inoperative or damaged EGR system
Inoperative or damaged VCT oil control solenoid(s)
Refer to the appropriate service information for the procedure. Refer toENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Inoperative or damaged ignition system Refer to the appropriate service information
Inoperative or damaged cooling system
Inoperative or damaged fuel system
Refer to the appropriate service information
Fail-safe cooling invoked (if equipped) Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Incorrect valve clearance ADJUST valve clearance. Refer to the appropriate article for the procedure. TEST the system for normal operation after the repair.
Incorrect valve-to-valve seat contact INSTALL a new cylinder head. For 2.7L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L 32VREFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Damaged head gasket For 2.7L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L 32VREFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Engine runs rough Inoperative or damaged fuel system
Air or vacuum leaks
EGR system fault
Inoperative or damaged cooling system
Inoperative or damaged ignition system
Inoperative or damaged VCT oil control solenoid(s)
Refer to the appropriate service information for the procedure. Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Fail-safe cooling invoked (if equipped) Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Burnt or sticking valve INSTALL a new valve. TEST the system for normal operation after the repair.
Weak or broken valve spring INSTALL a new valve spring. TEST the system for normal operation after the repair.
Carbon accumulation in combustion chamber ELIMINATE carbon buildup. TEST the system for normal operation after the repair.
Excessive oil consumption Leaking oil REPAIR oil leakage. TEST the system for normal operation after the repair.
Blocked or restricted turbocharger oil drain pipe INSPECT the turbocharger drain pipe. REPAIR as necessary. TEST the system for normal operation after the repair.
Damaged or collapsed air intake hoses and tubes Tighten hoses clamps. INSPECT for damage and REPAIR as necessary. TEST the system for normal operation after the repair.
Damaged exhaust or exhaust leaks at turbocharger housing or exhaust manifold. INSPECT for leaks. Leaks can be detected audibility or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as necessary. TEST the system for normal operation after the repair.
Turbocharger oil seals leaking REFER to Turbocharger Internal Oil Leak Test. REFER to: Turbocharger . or REFER to: Turbocharger . TEST the system for normal operation after the repair.
Inoperative PCV system REPAIR or INSTALL new components as necessary. TEST the system for normal operation after the repair.
Incorrect oil CHANGE oil to correct specification. TEST the system for normal operation after the repair.
Worn valve stem seal INSTALL a new valve stem seal. TEST the system for normal operation after the repair.
Worn valve stem or valve guide For 2.7L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L 32VREFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Sticking piston rings INSTALL new piston rings. TEST the system for normal operation after the repair.
Worn piston ring groove
Missing or damaged oil control ring
INSTALL a new piston and piston pin. TEST the system for normal operation after the repair.
Worn piston or cylinder INSTALL a new piston or cylinder block. TEST the system for normal operation after the repair.
Oil in coolant Leaking head gasket
Damaged cylinder block
Damaged cylinder head
INSPECT the engine components. INSTALL new engine components as necessary. Refer to the aappropriate service information. For 2.7L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L 32VREFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Leaking oil cooler INSPECT the oil cooler and seal for damage. INSTALL new components as necessary. For 2.7L REFER to: Oil Cooler . or REFER to: Oil Cooler . , For 3.5L REFER to: Oil Cooler - Raptor . or For 5.0L REFER to: Oil Cooler .
Coolant in oil Leaking head gasket
Damaged cylinder block
Damaged cylinder head
INSPECT the engine components. INSTALL new engine components as necessary. Refer to the appropriate service information. For 2.7L EcoBoost REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L Duratec-V6 , REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L, REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Leaking oil cooler INSPECT the oil cooler and seal for damage. INSTALL new components as necessary. REFER to: For 2.7L REFER to: Oil Cooler . or REFER to: Oil Cooler . , For 3.5L REFER to: Oil Cooler - Raptor . or For 5.0L REFER to: Oil Cooler .
Insufficient power Inoperative or damaged ignition system
Air intake system blockage
Lubrication system blockage
Inoperative or damaged fuel system
Inoperative or damaged TB (throttle body)
Refer to the appropriate articlefor the procedure. Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Turbocharger turbine or compressor wheel damage INSPECT the turbocharger. REFER to the Check for Free Rotation. REFER to: Turbocharger . or REFER to: Turbocharger . TEST the system for normal operation after the repair.
Damaged exhaust or exhaust leaks at turbocharger housing or exhaust manifold INSPECT for leaks. Leaks can be detected audibility or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as necessary. TEST the system for normal operation after the repair.
Malfunctioning turbocharger bypass valve Refer to ENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Oil level too high DRAIN oil to correct level.
Incorrect engine oil INSTALL correct specification engine oil. TEST the system for normal operation after the repair.
Excessive accessory drive belt loading
Inoperative or damaged cooling system
Refer to the appropriate service information.
Fail-safe cooling invoked (if equipped) Refer toENGINE CONTROLS - INTRODUCTION (EXCEPT DIESEL & HYBRID)
Damaged or plugged exhaust system INSPECT exhaust system. TEST the system for normal operation after the repair.
Incorrect tire size REFER to: Suspension System .
Dragging brakes REFER to: Brake System .
Slipping transmission Refer to the appropriate service information.
Slipping clutch Refer to the appropriate service information
Incorrect valve clearance ADJUST valve clearance. Refer to the appropriate article for the procedure. TEST the system for normal operation after the repair.
Worn or damaged valve tappet INSTALL a new valve tappet. TEST the system for normal operation after the repair.
Damaged valve guide
Compression leakage at valve seat
Seized valve stem
INSTALL a new cylinder head assembly. For 2.7L EcoBoost REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L Duratec-V6 , REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L, REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair TEST the system for normal operation after the repair.
Weak or broken valve spring INSTALL a new valve spring. TEST the system for normal operation after the repair.
Worn or damaged cam INSTALL a new camshaft. 2.7L REFER to: Camshaft LH . or REFER to: Camshaft RH . For 3.3L REFER to: Camshafts . For 5.0L REFER toCamshaft LH . or REFER to: Camshaft RH . TEST the system for normal operation after the repair.
Damaged head gasket INSTALL a new head gasket. REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L Duratec-V6 , REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L, REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Cracked or distorted cylinder head INSTALL a new cylinder head assembly. REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.3L Duratec-V6 , REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 3.5L, REFER to: Cylinder Head - Body Off - LH . or REFER to: Cylinder Head - Body Off - RH . For 5.0L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Damaged, worn or sticking piston ring(s) INSTALL a new piston ring(s). TEST the system for normal operation after the repair.
Worn or damaged piston INSTALL a new piston and piston pin. TEST the system for normal operation after the repair.
Engine emits excessive black smoke Clogged Air Cleaner (ACL) element INSTALL a new ACL element. TEST the system for normal operation after the repair.
Malfunctioning fuel injection system INSPECT the fuel injection system. REFER to: Fuel Charging and Controls . or or REFER to: Fuel Charging and Controls . or REFER to: Fuel Charging and Controls . TEST the system for normal operation after the repair.
Engine emits excessive white smoke Damaged cylinder head INSTALL a new cylinder head. For 2.7L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 5.0L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Damaged head gasket INSTALL a new cylinder head gasket. For 2.7L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . For 5.0L REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair.
Cracked engine block INSTALL a new engine. TEST the system for normal operation after the repair.
Condensation build up in exhaust Smoke dissipates after start up and doesn't continue after driving/running. Normal no repair needed.
Overheating engine INSPECT the cooling system.For 2.7L REFER to: Engine Cooling .. For 5.0L REFER to: Engine Cooling . REPAIR as necessary. TEST the system for normal operation after the repair.
Engine emits excessive blue smoke Engine wear (piston rings, valve guides) REPAIR as necessary. TEST the system for normal operation after the repair.
turbo Install a new turbo. For 2.7L REFER to: Turbocharger LH . or REFER to: Turbocharger RH . ; REFER to: TEST the system for normal operation after the repair.
Blocked or restricted turbocharger oil drain pipe INSPECT the turbocharger oil drain pipe. REPAIR as necessary. TEST the system for normal operation after the repair.
Turbocharger oil seals leaking REFER to Turbocharger Internal Oil Leak Test. REFER to: Turbocharger . or REFER to: TEST the system for normal operation after the repair.
Plugged crankcase ventilation system Visually INSPECT the crankcase ventilation system.
Worn valve seals REPAIR as necessary. TEST the system for normal operation after the repair.
Incorrect type or grade of oil DRAIN and FILL with specified oil.
Engine emits excessive gray smoke Blocked or restricted turbocharger oil drain pipe INSPECT the turbocharger oil drain pipe. REPAIR as necessary. TEST the system for normal operation after the repair.
Damaged/restricted or leaking turbocharger CAC assembly REPAIR or INSTALL a new CAC assembly as necessary. TEST the system for normal operation after the repair.
Plugged crankcase ventilation system Visually INSPECT the crankcase ventilation system.
Turbocharger oil seals leaking REFER to Turbocharger Internal Oil Leak Test. REFER to: Turbocharger . TEST the system for normal operation after the repair.
Transmission fluid burning on exhaust INSPECT the transmission for a leak. Refer to the appropriate service information. REPAIR as necessary. TEST the system for normal operation after the repair.
Black soot Exhaust tailpipe GTDI engines Normal condition from rich air/fuel mixture under low load conditions.
Low or no oil pressure after an oil change (2.7L GTDI only) Oil filter housing REMOVE the oil filter housing. INSPECT the oil filter housing for a missing or damaged center stem. INSPECT for a missing or damaged O-ring seal on the stem. REPAIR as necessary. TEST the system for normal operation after the repair.