Symptom Chart - Engine Performance
WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
| Symptom | Possible Sources | Action |
|---|---|---|
| Difficult starting | Inoperative or damaged glow plug system Inoperative or damaged fuel system Inoperative or damaged starting system |
Refer to the appropriate information in Engine System for the procedure. Refer to Engine Controls - Symptom Charts (Diesel) . |
| Damaged charging system/ battery | REFER to: Charging System - 6.7L Power Stroke Diesel . TEST the system for normal operation after the repair. | |
| Burnt valve | INSTALL a new cylinder head. 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. TEST the system for normal operation after the repair. | |
| Poor idling | Inoperative or damaged EGR system | Refer to the appropriate information in Engine System for the procedure. Refer to Engine Controls - Symptom Charts (Diesel) . |
| Inoperative or damaged cooling system Inoperative or damaged fuel system |
Refer to the appropriate information in Engine System for the procedure. | |
| Damaged hydraulic lash adjuster | INSTALL a new hydraulic lash adjuster. TEST the system for normal operation after the repair. | |
| Incorrect valve-to-valve seat contact | INSTALL a new cylinder head. TEST the system for normal operation after the repair. | |
| Damaged head gasket | INSTALL a new cylinder head gasket. TEST the system for normal operation after the repair. | |
| Engine runs rough | Inoperative or damaged fuel system Leaking or damaged CAC, intake manifold or gaskets EGR system fault Inoperative or damaged cooling system Malfunctioning or damaged air intake system |
Refer to the appropriate information in Engine System for the procedure. |
| Damaged hydraulic lash adjuster | INSTALL a new hydraulic lash adjuster. TEST the system for normal operation after the repair. | |
| 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. | |
| Worn valve guides, valves and seals | INSTALL a new cylinder head. 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. |
| Turbocharger oil seals leaking | REFER to Turbocharger Internal Oil Leak Test. REFER to: Turbocharger . TEST the system for normal operation after the repair. | |
| Malfunctioning crankcase vent oil separator | REPAIR or INSTALL new components as necessary. TEST the system for normal operation after the repair. | |
| Oil dilution (fuel) | 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. 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 | 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. | |
| Insufficient power | Air intake system blockage Boost leaks or blockage Inoperative or damaged fuel system |
Refer to the appropriate information in Engine System for the procedure. Refer to Engine Controls - Symptom Charts (Diesel) . |
| Turbocharger damage | INSPECT the turbocharger. REFER to the Check for Free Rotation-- On Vehicle. 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. | |
| 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. | |
| Low oil pressure | CARRY OUT the Oil Pressure Test . Compare to specifications, repair as necessary. TEST the system for normal operation after the repair. | |
| Excessive accessory drive belt loading Inoperative or damaged cooling system |
Refer to the appropriate information in Engine System for the procedure. | |
| Damaged or plugged exhaust system | INSPECT exhaust system. TEST the system for normal operation after the repair. | |
| Incorrect tire size | REFER to: Suspension System . TEST the system for normal operation after the repair. | |
| Dragging brakes | REFER to: Brake System . TEST the system for normal operation after the repair. | |
| Slipping transmission | Refer to the appropriate information in Automatic Transmission for the procedure. | |
| Malfunctioning hydraulic lash adjuster | INSTALL a new hydraulic lash adjuster. TEST the system for normal operation after the repair. | |
| Compression leakage at valve seat Seized valve stem |
INSTALL a new cylinder head. 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 camshaft | INSTALL a new camshaft. TEST the system for normal operation after the repair. | |
| Damaged head gasket | INSTALL a new head gasket. TEST the system for normal operation after the repair. | |
| Cracked or distorted cylinder head | INSTALL a new cylinder head. 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. | |
| Worn or damaged cylinder | INSPECT the cylinder for wear or damage. Repair as necessary. TEST the system for normal operation after the repair. | |
| Low oil pressure | Inaccurate gauge reading | DIAGNOSE the IPC. REFER to: Information Center - Instrumentation, Message Center And Warning Chimes . |
| Low oil level | ADJUST the oil level. | |
| Oil dilution (fuel) | INSPECT the fuel injectors. REFER to: Fuel Injectors . Repair as necessary. TEST the system for normal operation after the repair. | |
| Stuck open oil pressure regulator | INSTALL a new engine front cover. REFER to: Engine Front Cover . TEST the system for normal operation after the repair. | |
| Scored/damaged oil pump | INSTALL a new engine front cover. REFER to: Engine Front Cover . TEST the system for normal operation after the repair. | |
| Broken or damaged piston cooling tubes | REMOVE the upper oil pan. INSPECT the piston cooling tubes. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| 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 after the repair. | |
| Leaking/missing core plugs | INSPECT for leaking/missing core plugs. REFER to: Cylinder Block Core Plug Replacement . REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Worn/damaged/missing bearing shell(s) | CHECK the crankshaft main bearings and connecting rod bearings. CARRY OUT the REFER to: Crankshaft Main Bearing Journal Clearance . and REFER to: Connecting Rod Bearing Journal Clearance . REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Restriction in the pickup tube or oil pan | REMOVE the upper oil pan. INSPECT the oil pan and pickup tube. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| External oil leaks | INSPECT the engine for oil leaks. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Engine emits excessive black smoke (black/blue/white) | Clogged ACL (air cleaner) 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. | |
| 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. | |
| Oil in coolant | Damaged cylinder head gasket(s) | REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . INSPECT the cylinder head gasket(s). REPAIR as necessary. TEST the system for normal operation after the repair. |
| Damaged cylinder head(s) | REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . INSPECT the cylinder head(s). REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Damaged cylinder block | REFER to: Engine . INSPECT the cylinder block. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Leaking oil cooler | REFER to: Oil Cooler . INSPECT the oil cooler and gaskets for damage. INSTALL new components as necessary. TEST the system for normal operation after the repair. | |
| Coolant in oil | Damaged cylinder head gasket(s) | REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . INSPECT the cylinder head gasket(s). REPAIR as necessary. TEST the system for normal operation after the repair. |
| Damaged cylinder head(s) | REFER to: Cylinder Head LH . or REFER to: Cylinder Head RH . INSPECT the cylinder head(s). REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Damaged cylinder block | REFER to: Engine . INSPECT the cylinder block. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Leaking oil cooler | REFER to: Oil Cooler . INSPECT the oil cooler and gaskets for damage. INSTALL new components as necessary. TEST the system for normal operation after the repair. | |
| Leaking turbocharger base gasket. | REFER to: Turbocharger . INSPECT the turbocharger base gasket. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| RH valve cover or gasket. | REFER to: Valve Cover RH . INSPECT the valve cover and the gasket. REPAIR as necessary. TEST the system for normal operation after the repair. | |
| Engine front cover | REFER to: Engine Front Cover . INSPECT the engine front cover gaskets. REPAIR as necessary. TEST the system for normal operation after the repair. | |