Symptom Chart

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
Loss of power/performance	Clogged Air Cleaner (ACL) element	INSTALL a new Air Cleaner (ACL) element. TEST the system for normal operation.
Loose connections or damage to air intake hoses and tubes		TIGHTEN the hose clamps. INSPECT for damage. REPAIR as needed.
Malfunctioning fuel system		Refer to Engine Controls - Symptom Charts (Except Diesel & Hybrid)
Poor fuel quality		DRAIN the fuel. FILL with fresh fuel.
Engine wear (piston rings, valve guides)		REPAIR as needed.
Turbocharger turbine or compressor wheel damage		INSPECT the turbocharger. REFER to Check for Free Rotation -- On Vehicle .
Damaged exhaust or exhaust leaks at turbocharger housing		INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as needed.
Malfunctioning turbocharger bypass valve		Refer to Engine Controls - Symptom Charts (Except Diesel & Hybrid)
Obstructed wastegate actuator linkage		INSPECT the turbocharger wastegate linkage for obstructions. REPAIR as needed.
Damaged wastegate actuator linkage		INSPECT the turbocharger wastegate linkage for damage. INSTALL a new turbocharger as needed.
Wastegate actuator operation		TEST the wastegate actuator operation. Refer to Engine Controls - Symptom Charts (Except Diesel & Hybrid)
PCM (powertrain control module) -- DTC (diagnostic trouble code)		REFER to: Electronic Engine Controls .

Symptom	Possible Sources	Action
Excessive oil consumption	Incorrect type or grade of oil	DRAIN the oil. FILL with specified oil.
Oil in exhaust manifolds		REPAIR as needed.
Clogged Air Cleaner (ACL) element		INSTALL a new Air Cleaner (ACL) element. TEST the system for normal operation.
Blocked or restricted turbocharger oil drain tubes		INSPECT the turbocharger oil drain tube. REPAIR as needed.
Damaged or collapsed air intake hoses and tubes		TIGHTEN the hose clamps. INSPECT for damage. REPAIR as needed.
Damaged exhaust or exhaust leaks at turbocharger housing to cylinder head		INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as needed.
Turbocharger oil seals leaking		REFER to Turbocharger Internal Oil Leak Test .
Damaged crankcase ventilation system		Visually INSPECT the crankcase ventilation system. REPAIR as needed.

Symptom	Possible Sources	Action
Excessive noise	Turbocharger compressor air intake pipe leaking	REPAIR or INSTALL a new pipe as required.
Loose connections or damage to air intake hoses and tubes		TIGHTEN the hose clamps. INSPECT for damage. REPAIR as needed.
Air leaks at turbine housing, blown joints or damaged exhaust		INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as needed.
Carbon build up in the turbine housing causing contact with turbine wheel		INSPECT the turbocharger. REFER to the appropriate Engine article.
Turbocharger imbalance due to foreign object/damage		REPAIR as needed.
Inoperative turbocharger bypass valve		Refer to Engine Controls - Symptom Charts (Except Diesel & Hybrid)

Symptom	Possible Sources	Action
Engine emits excessive smoke (black/blue/white)	Clogged Air Cleaner (ACL) element	INSTALL a new Air Cleaner (ACL) element. TEST the system for normal operation.
Incorrect type or grade of oil		DRAIN the oil. FILL with specified oil.
Blocked or restricted turbocharger oil drain tubes		INSPECT the turbocharger oil drain tube. REPAIR as needed.
Damaged/restricted or leaking turbocharger compressor air intake pipe		REPAIR or INSTALL a new pipe as required.
Engine wear (piston rings, valve guides)		REPAIR as needed.
Plugged crankcase ventilation system		Visually INSPECT the crankcase ventilation system. REPAIR as needed.
Turbocharger oil seals leaking		REFER to Turbocharger Internal Oil Leak Test

Symptom	Possible Sources	Action
External oil leaks or oil tube leaks	Turbocharger oil tube seals and/or oil tube leaking	Visually INSPECT the turbocharger oil tubes and the turbocharger oil tube seals/gaskets. REPLACE the turbocharger oil tube seals/gaskets and the turbocharger oil tubes as needed.

Symptom	Possible Sources	Action
External coolant leaks or coolant tube leaks	Turbocharger coolant tube seals and/or coolant tube leaking	Visually INSPECT the turbocharger coolant tubes and the turbocharger coolant tube seals/gaskets. REPLACE the turbocharger coolant tube seals/gaskets and the turbocharger coolant tubes as needed.