Symptom Chart - Engine Performance
| 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 service information for the procedure. Refer to Engine Controls - Symptom Charts (Except Diesel & Hybrid) |
| Damaged charging system/ battery | REFER to: Charging System - 2.3L EcoBoost (231kW/314PS) . ; REFER to: Charging System - 5.0L 32V Ti-VCT . ; REFER to: Charging System - 5.2L 32V Ti-VCT . ; | |
| Burnt valve | INSTALL a new cylinder head.REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . 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. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . TEST the system for normal operation after the repair. | |
| Inoperative or damaged cooling system | Refer to the appropriate service information. | |
| Fouled spark plugs | INSTALL new spark plugs. REFER to: Spark Plugs . ; REFER to: Spark Plugs . ; REFER to: Spark Plugs . | |
| 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 to Engine Controls - Introduction (Except Diesel & Hybrid) |
| Inoperative or damaged ignition system | Refer to theappropriate service information for the procedure. | |
| Inoperative or damaged cooling system Inoperative or damaged fuel system |
Refer to the appropriate service information for the procedure. | |
| Fail-safe cooling invoked (if equipped) | Refer to Engine Controls - Introduction (Except Diesel & Hybrid) | |
| Incorrect valve clearance | ADJUST valve clearance. Refer to the appropriate service information for the procedure. TEST the system for normal operation after the repair. | |
| Incorrect valve-to-valve seat contact | INSTALL a new cylinder head. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . TEST the system for normal operation after the repair. | |
| Damaged head gasket | INSTALL a new cylinder head gasket. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . TEST the system for normal operation after the repair. | |
| Fouled spark plugs | INSTALL new spark plugs. REFER to: Spark Plugs . ; REFER to: Spark Plugs . ; REFER to: Spark Plugs . | |
| 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 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 . 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 | INSTALL a new cylinder head. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . 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 appropriate service information for the procedure. TEST the system for normal operation after the repair. |
| Leaking oil cooler | INSPECT the oil cooler and seal for damage. REFER to: Oil Cooler . REFER to: Oil Cooler . INSTALL new components as necessary. Refer to the appropriate service information for the procedure. | |
| Coolant in oil | Leaking head gasket Damaged cylinder block Damaged cylinder head |
INSPECT the engine components. INSTALL new engine components as necessary. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . Refer to the appropriate service information for the procedure. TEST the system for normal operation after the repair. |
| 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 service information for 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 . 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: Accessory Drive . ; REFER to: Accessory Drive . ; REFER to: Accessory Drive . Cooling system : REFER to: Engine Cooling . REFER to: Engine Cooling . REFER to: Engine . | |
| Fail-safe cooling invoked (if equipped) | Refer to Engine 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:IDENTIFICATION CODES Identification Codes (100-01 Identification Codes). | |
| 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 service information. 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. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . 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. REFER to: Camshafts . ; REFER to: Camshaft LH . or REFER to: Camshaft RH . ; REFER to: Camshaft LH . or REFER to: Cylinder Head RH . TEST the system for normal operation after the repair. | |
| Damaged head gasket | INSTALL a new head gasket. REFER to: Cylinder Head LH . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . 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 . REFER to: Cylinder Head RH . ; REFER to: Cylinder Head LH . 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 (black/blue/white) | Clogged Air Cleaner (ACL) element | INSTALL a new ACL element. TEST the system for normal operation after the repair. |
| Incorrect type or grade of oil | DRAIN and FILL with specified oil. REFER to: Engine Oil Draining and Filling . | |
| Blocked or restricted turbocharger oil drain pipe | INSPECT the turbocharger oil drain pipe. REPAIR as necessary REFER to: Turbocharger Oil Return Tube . . TEST the system for normal operation after the repair. | |
| Damaged/restricted or leaking turbocharger intake tube assembly | REPAIR or INSTALL a new tube as necessary. TEST the system for normal operation after the repair. | |
| Engine wear (piston rings, valve guides) | REPAIR 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. | |
| 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. |