Carb Question

10° is a fair amount of advance given that the factory spec is between 0° and 2.5°. It's not usually enough to cause a dieseling problem, but if there are other things contributing towards the problem, the extra advance will certainly not help. How's the idle quality? Smooth and even? Rough and shaky? Watch the engine as it idles and listen at the tailpipe for the spluttering sound of misfire that would point towards vacuum leaks or improper idle settings aggravating the problem.

The direct cause of dieseling is overly-hot combustion chambers. A lot of different things can heat them up. Anything that makes a cylinder run lean, for example, will heat it up. Carbon buildup in the combustion chamber will do the same, and a bit of carbon heated to incandescence will cause the dieseling effect.

Until you find and fix the problem(s), shut the car off before you shift into Park. The transmission load on the engine will drag it down to an immediate stop.