Don`t know if the problem I had is anything related to yours.
This was back in early 07. In the morning when first starting the engine I heard this ticking or slapping sound in the r/f of the engine. (pass side)
when the engine warmed up, it went away. wasn`t real loud, but could be heard.
Then in July 07 is when the timing chain let go at 65mph. not sure why, I had it replaced 70,000 prior to this.
your problem may be unrelated, but check things out reeeeel good.
500 miles was a loooooog way to push the car home

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Charlie