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Home >> Ford >> 2002 >> Cutaway 7.3 F >> Repair and Diagnosis >> External Pages >> Different car >> Section 2911 (Engine Mechanical - 6.7L Diesel -- F250-F550 Super Duty) >> Diagnosis And Testing >> Engine >> Symptom Chart - Engine NVH

Symptom Chart - Engine NVH

WARNING: This page is about a different car, the 2011 Ford Pickup, 2011 Ford F550 Super Duty, 2011 Ford F450 Super Duty, and 2011 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Engine NVH symptoms should be identified using the diagnostic tools that are available. For a list of these tools, an explanation of their uses and a glossary of common terms, refer to NOISE, VIBRATION & HARSHNESS article. Since it is possible that any one of multiple systems may be the cause of the symptom, it may be necessary to use a process of elimination type of diagnostic approach to pinpoint the responsible system. If this is not the causal system for the symptom, refer back to NOISE, VIBRATION & HARSHNESS article. for the next likely system and continue diagnosis.
SYMPTOM CHART - ENGINE NVH

Condition Possible Sources Action
  • Drone type noise
  • Powertrain mount(s)
  • Drumming noise - occurs inside the vehicle during idle or high idle, hot or cold. Very low-frequency drumming is very rpm dependent
  • Engine vibration excites the body resonances inducing interior noise
  • Engine drumming noise - accompanied by vibration
  • Powertrain mount(s)
  • Rattle - occurs at idle or at light acceleration from a stop
  • Powertrain mount(s)
  • Damaged flexplate
  • INSPECT the flexplate. REFER to FLEXPLATE INSPECTION  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Fuel injector stuck open
  • Whine/moan type noise - pitch increases or changes with vehicle speed
  • Powertrain mount(s)
  • Valvetrain/ Timing drive component noise
  • CARRY OUT the Valve Train Analysis  Component Test in this service information. REPAIR as necessary. TEST the system for normal operation
  • Clunk - occurs when shifting from PARK or between REVERSE and DRIVE
  • Powertrain mounts
  • Driveshaft universal joint
  • INSPECT the driveshaft universal joints. REFER to DRIVESHAFT article. REPAIR as necessary. TEST the system for normal operation.
  • Accessory drive bearing hoot - occurs at idle or high idle in cold temperatures of approximately +4°C (+40°F) or colder at the first start of the day
  • Accessory drive idler or tensioner pulley bearing is experiencing stick/slip between ball bearings and the bearing race
  • CARRY OUT the engine cold soak procedure. REFER to NOISE, VIBRATION & HARSHNESS article.
  • PLACE the EngineEAR probe directly on the idler/tensioner center post or bolt to verify which bearing is making the noise. REFER to ENGINE ACCESSORY DRIVE BELTS article. REPAIR as necessary. TEST the system for normal operation.
  • Accessory drive belt noise, squeal or chirping
  • Defective/worn or incorrect accessory drive belt
  • Misaligned pulley(s)
  • Pulley runout
  • Damaged or worn accessory drive component or idler
  • Fluid contamination of the accessory drive belt or pulleys
  • Damaged or worn accessory drive belt tensioner
  • Damaged pulley grooves
  • Clunking noise
  • Coolant pump has excessive end play or imbalance
  • CHECK the coolant pump for excessive end play. REFER to ENGINE COOLING - DIESEL ENGINE article. INSPECT the coolant pump for imbalance with the drive belt off. REPAIR as necessary. TEST the system for normal operation.
  • Whine or moaning noise
  • Air intake system
  • Boost leak
  • Excessive turbocharger noise
  • Whistling noise
  • Turbocharger inlet pipes
  • Inspect the turbocharger inlet pipes. REFER to EXHAUST SYSTEM article. REPAIR as necessary. TEST the system for normal operation.
  • EGR cooler pipes
  • INSPECT the EGR cooler pipes. REFER to EMISSION CONTROL SYSTEM article. REPAIR as necessary. TEST the system for normal operation.
  • Hissing noise - occurs during idle or high idle that is apparent with the hood open
  • Boost leak noise
  • USE the EngineEAR to locate the source. SCAN the air intake system from the inlet to each cylinder intake port. DISCARD the leaking parts, and INSTALL a new component.
  • Composite intake manifold
  • Acceptable condition. Some composite manifolds exhibit this noise, which is the effect of the composite manifold.
  • Grinding noise - occurs during engine cranking
  • Incorrect starter motor mounting
  • INSPECT the starter motor for correct mounting. REFER to STARTING SYSTEM - DIESEL ENGINE article. REPAIR as necessary. TEST the system for normal operation.
  • Starter motor
  • Incorrect starter motor drive engagement
  • INSPECT the starter motor drive for wear or damage. REFER to STARTING SYSTEM - DIESEL ENGINE article. REPAIR as necessary. TEST the system for normal operation.
  • Damaged flexplate
  • INSPECT the flexplate. REFER to FLEXPLATE INSPECTION  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, front of engine - knocking noise from lower front of engine
  • Damaged or separated crankshaft pulley/damper
  • CHECK for obvious signs of damage or wobble during operation. REFER to CRANKSHAFT PULLEY  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, front of engine - ticking, tapping or rattling noise from the front of the engine
  • Timing drive components
  • Damaged oil pump
  • REMOVE the accessory drive belt. REFER to ENGINE ACCESSORY DRIVE BELTS article.
  • USE the EngineEAR to isolate the noise to the engine front cover.
  • REMOVE the engine front cover and INSPECT the timing drive components and oil pump. REFER to ENGINE FRONT COVER  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, upper end - ticking noise near the fuel rail
  • Fuel injector
  • Engine noise, upper end - ticking, knocking or rattle noise that occurs during idle or high idle during the first cold start of the day and may disappear as the engine warms
  • Valve train noise (bled down hydraulic lash adjuster)
  • CARRY OUT the Valve Train Analysis  Component Test in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, upper end - rattling noise from the valve train. Worse when the engine is cold
  • Low oil level
  • CHECK the oil level. FILL as necessary.
  • Worn valve train components
  • CARRY OUT the Valve Train Analysis  Component Test in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Worn valve guides
  • CARRY OUT the Valve Guide Inner Diameter  procedure in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Excessive runout of the valve seats on the valve face
  • CARRY OUT the Valve Seat Inspection  procedure in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, upper end - knocking or ticking noise, occurs mostly with a warm engine at idle
  • Low oil level
  • CHECK the oil level. FILL as necessary.
  • Thin or diluted oil
  • INSPECT the oil for contamination. If the oil is contaminated, CHECK for the source. REPAIR as necessary. CHANGE the oil and filter.
  • Incorrect oil viscosity
  • DRAIN the oil. REFILL with the proper viscosity oil for the climate.
  • Damaged or incorrect oil filter
  • INSPECT the oil filter. INSTALL a new oil filter as necessary.
  • Low oil pressure
  • CARRY OUT the Oil Pressure Test in this service information. If not within specifications, GO to the LOW OIL PRESSURE TEST  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, lower end - ticking or knocking noise at engine front cover
  • Oil pump
  • USE the EngineEAR to verify the oil pump as the source of the noise at low rpm. INSTALL a new engine front cover. REFER to ENGINE FRONT COVER  in this service information. TEST the system for normal operation.
  • Engine noise, lower end - light knocking noise, also described as piston slap. Noise is most noticeable when the engine is cold with light to medium acceleration. The noise disappears as the engine warms
  • Excessive clearance between the piston and the cylinder wall
  • Engine noise, lower end - light double knock or sharp rap sound. Occurs mostly with a warm engine at idle or low speeds in drive. Increases in relation to engine load. Associated with a poor lubrication history
  • Excessive clearance between the piston and the piston pin
  • CARRY OUT the Piston Inspection  procedure in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine noise, lower end - light knocking noise. The noise is most noticeable when the engine is warm. The noise tends to decrease when the vehicle is coasting or in NEUTRAL
  • Excessive clearance between the connecting rod bearings and the crankshaft
  • Engine noise, lower end - deep knocking noise. The noise is most noticeable when the engine is warm, at lower rpm and under a light load and then at float
  • Worn or damaged crankshaft main bearings
  • Engine noise, rear of engine - knocking noise at rear of engine
  • Damaged flexplate
  • INSPECT the flexplate. REFER to FLEXPLATE INSPECTION  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Engine vibration - vibration felt at all times
  • Excessive crankshaft pulley runout
  • CARRY OUT the crankshaft pulley runout check. REFER to CRANKSHAFT PULLEY  in this service information. REPAIR as necessary. TEST the system for normal operation.
  • Damaged or worn accessory drive component
  • Engine vibration - at idle, a low-frequency vibration (5-20 Hz) or mild shake that is felt through the seat/floorpan
  • Cylinder misfire
  • CARRY OUT the Power Balance Test and the Relative Compression Test using the scan tool. REFER to INTRODUCTION article. REPAIR as necessary. TEST the system for normal operation.
  • Engine or torque converter out of balance
  • VERIFY the torque converter to crankshaft pilot clearance is correct. REFER to AUTOMATIC TRANSAXLE/TRANSMISSION - TORQSHIFT6 article. RE-INDEX the torque converter on the flexplate by 180 degrees. TEST the system for normal operation.
  • Engine vibration - is felt with increases and decreases in engine rpm
  • Powertrain mount(s)
  • Engine or transmission contacting the chassis
  • Engine vibration - increases intensity as the engine rpm is increased
  • Engine out-of-balance