Symptom Chart - 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: 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 . Since it is possible any one of multiple systems may be the cause of a 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 for the next likely system and continue diagnosis.

SYMPTOM CHART - NVH

Condition	Possible Sources	Action
Steering system cold start noise	Blockage in the power steering fluid reservoir caused by power steering fluid contamination Air in the steering hydraulic system (aerated fluid)	NOTE: Some noise during an extremely cold start (-12.2°C [-10°F]) is normal and should improve as the steering system warms up (usually within 60 seconds). NOTE: It may be necessary to remove the power steering fluid reservoir to flush contamination trapped in the reservoir screen. CHECK the power steering fluid reservoir for contamination. FLUSH the power steering system as necessary. REFER to POWER STEERING SYSTEM FLUSHING . CHECK for leaks in the system. REFER to POWER STEERING LEAK TEST Component Test. PURGE the air from the system. REFER to POWER STEERING SYSTEM PURGING .
Steering grunt or shudder - occurs when turning into or out of a turn at low speeds (temperature sensitive)	Air in the steering hydraulic system (aerated fluid) Steering gear or power steering hoses	CHECK for leaks in the system. REFER to POWER STEERING LEAK TEST Component Test. PURGE the air from the system. REFER to POWER STEERING SYSTEM PURGING . GO to STEERING GEAR GRUNT/SHUDDER Component Test.
Steering system clonk - hydraulic knocking sound	Air in the steering hydraulic system (aerated fluid)	NOTE: Some amount of clonk noise is considered acceptable. If in doubt of the acceptability, compare to another vehicle. CHECK for leaks in the system. REFER to POWER STEERING LEAK TEST Component Test. PURGE the air from the system. REFER to POWER STEERING SYSTEM PURGING .
Power steering pump moan - loud humming noise occurs when the steering wheel is rotated to the stop position. Produces a 120-600 Hz frequency that changes with rpm	Low fluid Air in the steering hydraulic system (aerated fluid) Power steering fluid reservoir or screen is blocked or damaged Power steering line/hose grounded to chassis Steering gear isolators	CHECK the fluid level. FILL as necessary. REFER to POWER STEERING SYSTEM FILLING . CHECK for leaks in the system. REFER to POWER STEERING LEAK TEST Component Test. PURGE the air from the system. REFER to POWER STEERING SYSTEM PURGING . If a pump moan still exists, INSTALL a new power steering pump. REFER to POWER STEERING SYSTEM SERVICING . REMOVE the reservoir. REFER to POWER STEERING SYSTEM SERVICING . FLUSH or INSTALL a new reservoir as necessary. INSPECT the power steering lines/hoses. REPAIR as necessary. INSPECT the isolators for wear or damage. REPAIR as necessary.
Steering gear clunk - occurs only while cornering over a bump (can be temperature sensitive)	Steering gear	INSPECT the steering gear for loose mounting bolts. TIGHTEN to specification as necessary. REFER to POWER STEERING SYSTEM SERVICING .
Feedback (rattle, chuckle or knocking noise in the steering gear) - roughness is felt in the steering wheel when the vehicle is driven over rough surfaces	Steering column shaft/coupling joints damaged or worn Loose, damaged or worn tie-rod ends Steering gear mounting bolts loose Steering column shaft/coupling bolts are loose Steering column damaged or worn	INSTALL a new steering column shaft. REFER to STEERING COLUMN . INSPECT and INSTALL new tie-rod ends as necessary. GO to STEERING LINKAGE Component Test. TIGHTEN the bolts to specification or INSTALL new bolts as necessary. REFER to POWER STEERING SYSTEM SERVICING . TIGHTEN the bolts to specification. REFER to STEERING COLUMN . REPAIR or INSTALL a new steering column as necessary. REFER to STEERING COLUMN .
Accessory drive belt squeal/chirp - when rotating the steering wheel from stop-to-stop	Engine accessory drive system	REFER to ENGINE MECHANICAL SYSTEM - GENERAL INFORMATION to continue accessory drive system diagnosis.
Power steering hiss or whistle	Steering column shaft/coupling-to-steering gear is binding or misaligned Grounded or loose steering column boot at the dash panel Damaged or worn steering gear input shaft and valve Restricted power steering lines/hoses	REPAIR or INSTALL a new steering column shaft as necessary. REFER to STEERING COLUMN . REPAIR as necessary. INSTALL a new steering gear as necessary. REFER to POWER STEERING SYSTEM SERVICING . GO to PINPOINT TEST A .
Steering column rattle	Loose bolts or attaching brackets Loose, worn or insufficiently lubricated column bearings Steering shaft insulators damaged or worn Steering column shaft/coupling compressed or extended	TIGHTEN the bolts to specification. LUBRICATE bearings or INSTALL new steering column bearings or steering column as necessary. REFER to STEERING COLUMN . INSTALL new insulators. REFER to STEERING COLUMN . INSPECT the rubber spider coupling for damage. INSTALL a new steering column shaft. REFER to STEERING COLUMN .
Steering gear squeak	Incorrect power steering fluid in system Steering gear seals Stone shield (if equipped)	If incorrect power steering fluid is suspected, FLUSH the power steering system. REFER to POWER STEERING SYSTEM FLUSHING . If noise persists after system flush, INSTALL new steering gear seals as necessary. REFER to Disassembly and Assembly in POWER STEERING SYSTEM SERVICING . INSTALL new steering gear seals as necessary. REFER to Disassembly and Assembly in POWER STEERING SYSTEM SERVICING . NOTE: Use the chassis ears to verify that the steering gear is the source of the noise. It may be necessary to replicate the customer operating conditions (fluid temperature, turning rate of steering wheel) to get the squeak to reoccur. Make sure that the stone shield is correctly installed and that it is not making contact with the steering shaft. REPOSITION stone shield or INSTALL a new stone shield as necessary.
Steering column squeak, cracks or grinds	Insufficiently lubricated steering shaft bushings Loose or misaligned steering column shrouds Steering wheel rubbing against steering column shrouds Upper or lower bearing sleeves out of position	LUBRICATE the steering shaft and shaft tube seals. TIGHTEN or ALIGN the steering column shrouds. REPOSITION the steering column shrouds. REPOSITION the bearing sleeves.
Power steering pump noisy	Power steering pump	INSTALL a new power steering pump as necessary. REFER to POWER STEERING SYSTEM SERVICING .
Power steering pump relief noise	Power steering fluid flow into the bypass valve of the pump valve housing, with fluid temperature below 54°C (130°F)	Acceptable condition.
Power steering pump whine noise	Aerated fluid Damaged power steering pump	CHECK for a leak in the system. REFER to POWER STEERING FLUID LEAK TEST Component Test. PURGE the air from the system. REFER to POWER STEERING SYSTEM PURGING . INSTALL a new power steering pump as necessary. REFER to POWER STEERING SYSTEM SERVICING .
High speed shake or shimmy	Worn or damaged steering linkage components	GO to STEERING LINKAGE Component Test.