Bad Jeep casting causes whistle
This bulletin applies to 2007 Jeep Liberty, Grand Cherokee and Commander (as well as light-duty Ram trucks, Dakota, Nitro and Durango vehicles). The intake-to-throttle body joint may cause a whistle-like sound on the 3.7L engine.
The customer may experience a slight high frequency whistle-like sound while driving. This sound is not loud and may not be noticed by some drivers. The sound can occur at any ambient or engine temperature. The sound is most noticeable under load with a light throttle, between 1,200 and 2,000 rpm.
1. Disconnect and isolate the negative battery cable from the battery.
2. Remove the electronic throttle control (ETC) throttle body from the intake manifold.
3. Apply a very small diameter bead (1 mm) of RTV to the intake manifold-to-throttle body joint. The RTV will be applied to the lower section of the joint between the lower two throttle body attachment holes. The gap was created by a slight taper in the intake manifold joint surface. Do not apply an excessive amount of RTV to the joint. Chrysler recommends RTV P/N 04883971.