06 Acura TL Squealing when accelerating

It is probably power steering noise, there is a known problem with air ingestion though an inlet O-ring.

Honda/Acura bulletin:

Applies To: _
_ 2004-07 TL - ALL

Under REPAIR PROCEDURE, a note was added to check the color of the inlet joint 0-ring if the vehicle was previously repaired under S/B 08-016.*

SYMPTOM

A moan or whine is heard when turning the steering wheel when the engine is cold. There may be air bubbles or foam in the power steering reservoir. The noise usually goes away when the engine warms up.

PROBABLE CAUSE

Air is entering the power steering pump through the inlet joint 0-ring. This causes bubbles to form in the power steering fluid, leading to reduced pump performance.

CORRECTIVE ACTION

Replace the 0-ring on the power steering pump inlet joint.