Symptom Chart - NVH

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods, Description and Operation Service Information .

Symptom Chart - NVH

Condition	Possible Sources	Action
NOTE: NVH symptoms will 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 and 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 and Harshness for the next likely system and continue diagnosis.
Excessive hissing from the plenum when the A/C is on	Low refrigerant charge	CHECK the A/C system for leaks. REFER to Fluorescent Dye Leak Detection or Electronic Leak Detection . RECHARGE the A/C system. REFER to Air Conditioning (A/C) System Recovery, Evacuation and Charging .
Noisy A/C compressor	A/C compressor clutch air gap out of specification	CHECK and ADJUST the A/C compressor clutch gap if necessary. REFER to Air Conditioning (A/C) Clutch Air Gap Adjustment . TEST the system for normal operation. If the A/C compressor clutch gap is OK, INSTALL a new A/C compressor clutch. REFER to Climate Control . TEST the system for normal operation.
A/C compressor pulley bearing worn		INSPECT the A/C compressor pulley bearing for roughness. If bearing roughness is found, INSTALL a new A/C compressor pulley. REFER to Climate Control . TEST the system for normal operation.
A/C compressor bearing worn		INSPECT the A/C compressor bearing for roughness. If bearing roughness is found, INSTALL a new A/C compressor. REFER to Climate Control . TEST the system for normal operation.