1981 300TD

Recently, my wagon has started to idle very rough and die if it idles for too long. Strange thing is that it purrs when I start it up and runs well until it gets to operating temps. Once it gets to about 90, it starts to lope and puff smoke.

I'm losing compression in a couple cylinders. #4 is at 232 and #5 is at 261. That test was done about 2,000 miles/1 year ago. It's not my primary vehicle and I don't drive it much. I know it's only a matter of time before the compression loss gets the best of me, but this seems like something else.

Any ideas?

Thanks.

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1981 300TD
1986 300SDL