Unusual missing problem
 

Hi, First time poster here! Looks like a great site!

I have a 1982 chevy 6.2L diesel w/~350 kmiles on it. Last week a very funny problem started. When I start the truck, on about 40% of the starts the engine runs just fine, but on about 60% of the starts it misses on one cylinder (as near as I can tell). Once it is started, if it is running fine, it never starts missing. Conversely, if at start-up it is missing, it will miss continually until the engine is restarted! On restarts, the 60/40 ratio seems to apply.

Any ideas on what could be going on?

Thanks