So, I have a 1988 240DL named Betsy by the little old lady we bought her from (literally). 149,000 miles. When slowing down to a stop, sometimes it stalls. Or, when starting from a stop, sometimes there is hardly any power. The engine doesn't rev even though the gas pedal is floored. Doesn't happen all the time. No rhyme or reason. What we usually do is while it is coasting, we throw it into neutral, turn off the engine, turn the engine back on, and we are good to go.

What do I tell my backyard mechanic? Thanks!