303-04C Fuel Charging and Controls - Turbocharger - 1.6L EcoBoost (132kW/180PS) - Sigma 2014 Fiesta
Diagnosis and Testing Procedure revision date: 05/1/2013

Turbocharger


General Equipment
Ford diagnostic equipment

Principles of Operation

The turbocharger is an exhaust-driven centrifugal air compressor. Its purpose is to increase power output by supplying compressed air to the engine.

Expanding exhaust gases drive the turbine shaft assembly to speeds up to 200,000 rpm. Filtered air entering the compressor side of the turbocharger is compressed and delivered through a Charge Air Cooler (CAC). The very hot compressed air is cooled, then continues on to fill the intake manifold at a higher pressure than atmospheric pressure. Because considerably more air is forced into the intake manifold, the results are increased power, fuel efficiency and the ability to maintain power at higher altitudes.

The turbocharger is governed by a wastegate actuator. The wastegate actuator redirects some of the exhaust gas past the turbine and therefore acts as a governor. The wastegate actuator is preset during manufacture and must not be tampered with. The wastegate actuator is controlled by the turbocharger control valve.

The intake air system is fitted with a turbocharger bypass valve. This vents the intake air system when the throttle is closed and recirculates the air back into the intake air system. It also releases pressure on the turbocharger which will reduce turbo lag and improve acceleration and increase engine performance.

The turbocharger is equipped with a boost control system. The PCM detects 1st or 2nd gear using the engine speed and vehicle speed signals. This information is then used to adjust the pressures applied to the wastegate actuator allowing it to open at a lower boost pressure. This prevents the turbocharger developing maximum boost in 1st and 2nd gears.

The turbocharger housing is both water and oil cooled. The oil supply also lubricates the turbocharger bearings.

Inspection and Verification

NOTE: This section provides mechanical diagnosis of the turbocharger assembly. If there is a Malfunction Indicator Lamp (MIL) illuminated, or Diagnostic Trouble Codes (DTCs) are present, these should be diagnosed prior to performing turbocharger mechanical diagnosis.

  1. For PCM Diagnostic Trouble Codes (DTCs),
    REFER to: Electronic Engine Controls (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Diagnosis and Testing).
    See MIL Code List. For driveability symptoms without Diagnostic Trouble Codes (DTCs), Refer to Powertrain Control/Emissions Diagnosis (PC/ED) manual. See Section 3 Symptom Charts.
  1. Verify the customer concern.
  1. Visually inspect for obvious signs of mechanical or electrical damage.


  Visual Inspection Chart


Mechanical Electrical
  • Oil leak(s)
  • Coolant leak(s)
  • Wastegate actuator
  • Wastegate actuator vacuum hose(s)
  • Wastegate valve
  • Turbocharger housing
  • Air Cleaner (ACL) element
  • Air Cleaner (ACL) outlet pipe
  • Air Cleaner (ACL) intake pipe
  • Turbocharger intake tube
  • Charge Air Cooler (CAC)
  • Charge Air Cooler (CAC) intake pipe
  • Charge Air Cooler (CAC) outlet pipe
  • Turbocharger oil supply tube
  • Turbocharger oil return tube
  • Turbocharger coolant supply tube
  • Turbocharger coolant return tube
  • Wiring harness(es)
  • Electrical connector(s)
  • Turbocharger control valve
  • PCM


  1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  1. If the concern is not visually evident, verify the symptom and refer to the Diagnostic Tab in the Ford diagnostic equipment.

Symptom Chart

Symptom Possible Sources Action
  • Loss of power/performance
  • Clogged Air Cleaner (ACL) element
  • Loose connections or damage to air intake hoses and tubes
  • Malfunctioning fuel system
  • Poor fuel quality
  • Engine wear (piston rings, valve guides)
  • Turbocharger turbine or compressor wheel damage
  • Damaged exhaust or exhaust leaks at turbocharger housing
  • Malfunctioning turbocharger bypass valve
  • Obstructed wastegate actuator linkage
  • Damaged wastegate actuator linkage
  • Wastegate actuator operation
  • PCM — Diagnostic Trouble Codes (DTCs)
  • INSTALL a new Air Cleaner (ACL) element. TEST the system for normal operation.
  • TIGHTEN the hose clamps. INSPECT for damage and REPAIR as necessary.
  • Refer to Powertrain Control/Emissions Diagnosis (PC/ED) manual.
  • DRAIN and FILL with fresh fuel.
  • REPAIR as required.
  • INSPECT the turbocharger. REFER to the Check for Free Rotation — Off Vehicle in this section.
  • INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as required.
  • Refer to Powertrain Control/Emissions Diagnosis (PC/ED) manual.
  • INSPECT the turbocharger wastegate linkage for obstructions. REPAIR as required.
  • INSPECT the turbocharger wastegate linkage for damage. INSTALL a new turbocharger as necessary.
  • TEST the wastegate actuator operation. Refer to Powertrain Control/Emissions Diagnosis (PC/ED) manual.

  • REFER to: Electronic Engine Controls (303-14B Electronic Engine Controls - 1.6L EcoBoost (132kW/180PS) - Sigma, Diagnosis and Testing).
    See MIL Code List.
Symptom Possible Sources Action
  • Excessive oil consumption
  • Incorrect type or grade of oil
  • Oil in the cylinder head to turbocharger flange
  • Clogged Air Cleaner (ACL) element
  • Blocked or restricted turbocharger oil drain tube
  • Damaged or collapsed air intake hoses and tubes
  • Damaged exhaust or exhaust leaks at turbocharger housing to cylinder head
  • Turbocharger oil seals leaking
  • Damaged crankcase ventilation system
  • DRAIN and FILL with specified oil.
  • REPAIR as required.
  • INSTALL a new Air Cleaner (ACL) element. TEST the system for normal operation.
  • INSPECT the turbocharger oil drain tube. REPAIR as necessary.
  • TIGHTEN hose clamps. INSPECT for damage and REPAIR as necessary.
  • INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as required.
  • REFER to Turbocharger Internal Oil Leak Test in this section.
  • Visually INSPECT the crankcase ventilation system. REPAIR as necessary.
Symptom Possible Sources Action
  • Excessive noise
  • Turbocharger compressor air intake pipe leaking
  • Loose connections or damage to air intake hoses and tubes
  • Air leaks at turbine housing, blown joints or damaged exhaust
  • Carbon build up in the turbine housing causing contact with turbine wheel
  • Turbocharger imbalance due to foreign object/damage
  • Turbine bearing failure
  • Inoperative turbocharger bypass valve
  • REPAIR or INSTALL a new pipe as required.
  • TIGHTEN hose clamps. INSPECT for damage and REPAIR as necessary.
  • INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as required.
  • INSPECT the turbocharger. REFER to the Check for Free Rotation — Off Vehicle in this section.
  • REPAIR as required.
  • INSPECT the turbocharger. REFER to the Check for Free Rotation — Off Vehicle in this section.
  • Refer to Powertrain Control/Emissions Diagnosis (PC/ED) manual.
Symptom Possible Sources Action
  • Engine emits excessive smoke (black/blue/white)
  • Clogged Air Cleaner (ACL) element
  • Incorrect type or grade of oil
  • Blocked or restricted turbocharger oil drain tube
  • Damaged/restricted or leaking turbocharger compressor air intake pipe
  • Engine wear (piston rings, valve guides)
  • Plugged crankcase ventilation system
  • Turbocharger oil seals leaking
  • INSTALL a new Air Cleaner (ACL) element. TEST the system for normal operation.
  • DRAIN and FILL with specified oil.
  • INSPECT the turbocharger oil drain tube. REPAIR as necessary.
  • REPAIR or INSTALL a new pipe as required.
  • REPAIR as required.
  • Visually INSPECT the crankcase ventilation system. REPAIR as necessary.
  • REFER to Turbocharger Internal Oil Leak Test in this section.

Component Tests

Turbocharger Internal Oil Leak Test

NOTE: It is normal for a small amount of combustion gas to pass into the crankcase. This gas is scavenged into the air intake system through the PCV system, which incorporates an crankcase vent oil separator. Some engine oil, in the form of a vapor is carried into the air intake system with the blow-by gases (this engine oil also contributes to valve seat durability). This means that oil will collect inside the air intake components and the turbocharger. This is not an indication that the turbocharger oil seal has failed. The turbocharger oil seal will not fail unless the bearings fail first, which will cause the turbocharger to become noisy or seize. Do not install a new turbocharger due to oil inside the turbocharger or the air intake components. If a leak is detected in the oil supply or return tubes or connections, locate and rectify the source. Do not install a new turbocharger due to an oil leak.

Check the turbocharger compressor inlet for evidence of oil. If excessive oil is present, this indicates that the failure could be in the engine or turbocharger.
REFER to: Engine (303-00 Engine System - General Information, Diagnosis and Testing).
or the following turbocharger check. If excessive oil is found in the turbocharger compressor outlet, check the Charge Air Cooler (CAC) for oil contamination. If contamination is present, flush the Charge Air Cooler (CAC).

Check the turbocharger turbine outlet for evidence of oil. If excess liquid oil is present in the outlet, remove the turbocharger from the engine and examine the oil supply and return passages in the turbocharger, engine block and the turbocharger oil drain tube for restriction. If no restriction is found, install a new turbocharger.
REFER to: Turbocharger (303-04C Fuel Charging and Controls - Turbocharger - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).

Check for Free Rotation — Off Vehicle

NOTE: The turbocharger must be pre-oiled before carrying out this check.

NOTE: Turbine and compressor wheels must spin freely when turned by hand. No housing contact is permitted.

Inspect the turbocharger compressor and turbine fins for damage. If the compressor or turbine wheel fins are damaged, install a new turbocharger.
REFER to: Turbocharger (303-04C Fuel Charging and Controls - Turbocharger - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).

Rotate the turbocharger shaft, listen for bearing noise and roughness. If there is bearing noise or roughness a install a new turbocharger.
REFER to: Turbocharger (303-04C Fuel Charging and Controls - Turbocharger - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).

Press and rotate the turbocharger shaft. If either the compressor wheel or the turbine wheel contacts the housing, the bearings are bad and a new turbocharger must be installed.
REFER to: Turbocharger (303-04C Fuel Charging and Controls - Turbocharger - 1.6L EcoBoost (132kW/180PS) - Sigma, Removal and Installation).



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