Idling should not cause that, but if it was low on oil it may have starved the upper end, causing flow issues.

The V8's are thirsty at idle.....I'd guess even on a totally full tank, that a 380 could not idle for more than 20 hours or so....maybe even less than that. Idling for a day, while not exactly good for the motor, shouldn't kill it either.

Replacing the cam shafts is $2500?? Yikes.....what amount of that is labor vs. parts cost? Two new camshafts are probably not more than $150 apiece new....and much less for a good used one.

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