One problem related to engine rattling and whining sounds has been reported for the 2006 Toyota Prius. The most recently reported issues are listed below.
Tl the contact owns a 2006 Toyota Prius. While driving, a whistling noise was heard coming from the engine. In addition, the check engine, abs reqd, air bag, and brake warning indicators illuminated. The vehicle was not taken to a dealer or an independent mechanic for diagnostic testing. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 232,000.