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 element	INSTALL a new air cleaner 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 (Diesel) .
Poor fuel quality		DRAIN the fuel system. FILL with fresh fuel.
Engine wear (piston rings, valve guides)		REPAIR as required.
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 required.
Obstructed VNT actuator linkage		INSPECT the turbocharger VNT linkage for obstructions. REPAIR as required.
Damaged VNT actuator linkage		INSPECT the turbocharger VNT linkage for damage. INSTALL a new turbocharger as needed.
VNT actuator operation		TEST the VNT actuator operation. Refer to ENGINE CONTROLS - INTRODUCTION (DIESEL) .
Turbocharger vanes inoperative		Inspect the turbocharger for oil varnished/stuck turbocharger vanes. REPAIR, to free up stuck turbocharger vanes, run vehicle at freeway speed for 30 minutes. Verify that the turbocharger vanes are no longer stuck and boost is normal. INSTALL a new turbocharger as needed.
PCM -- DTC		REFER to: Electronic Engine Controls .

Symptom	Possible Sources	Action
Excessive oil consumption	Incorrect type or grade of oil	DRAIN the oil. FILL with the specified oil.
Oil in the cylinder head to turbocharger flange		REPAIR as required.
Clogged air cleaner element		INSTALL a new air cleaner element. TEST the system for normal operation.
Blocked or restricted turbocharger oil drain tube		INSPECT the turbocharger oil drain tube. REPAIR as needed.
Damaged or collapsed air intake hoses and tubes		INSPECT for damage. REPAIR as needed.
Damaged exhaust or exhaust leaks at turbocharger housing to exhaust manifold		INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as required.
Turbocharger oil seals leaking		REFER to Turbocharger Internal Oil Leak Test .
Damaged crankcase ventilation system		INSPECT, visually 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 required.
Carbon build up in the turbine housing causing contact with turbine wheel		INSPECT the turbocharger. REFER to Check for Free Rotation -- On Vehicle .
Turbocharger imbalance due to foreign object/damage		REPAIR as required.

Symptom	Possible Sources	Action
Engine emits excessive smoke (black/blue/white)	Clogged air cleaner element	INSTALL a new air cleaner element. TEST the system for normal operation.
Incorrect type or grade of oil		DRAIN the oil. FILL with the specified oil.
Blocked or restricted turbocharger oil drain tube		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 required.
Plugged crankcase ventilation system		INSPECT, visually 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	INSPECT, visually 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.
Turbocharger vanes inoperative		Inspect the turbocharger for oil varnished/stuck turbocharger vanes. REPAIR, to free up stuck turbocharger vanes, run vehicle at freeway speed for 30 minutes. Verify that the turbocharger vanes are no longer stuck and boost is normal. INSTALL a new turbocharger as needed.

Symptom	Possible Sources	Action
External coolant leaks or coolant tube leaks	Turbocharger coolant tube seals and/or coolant tube leaking	INSPECT, visually 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.