Rough running at startup
 

Visited my stepson and we went to do some errands in his 82 SC. On each startup, car shook dramatically for a few seconds before settling down as first gear was selected and we started to move. Seemed like the engine was running incredibly rough during those first few seconds. Any ideas?

Did this problem occur suddenly or gradually? Does it occur during hot starts, warm starts, or cold starts? How many miles on the car? Any recent work that might have caused the problem?

Rough running
 

PeteKz, We drove the car to two or three stops. The rough running happened when starting from cold and hot. Don't know the exact mileage but under 100K. No work done recently. The car isn't driven all that often and for only short periods so my initial thought was a fouled plug. But I don't think that would clear itself after only a few seconds. Again, very rough on start-up and engine shakes dramatically for the first number of seconds. Appreciate any ideas.

Ethanol fuel if it sits?

Since you don't drive it often, it could be old fuel and deposit buildup in the fuel system or injectors. Before launching into a long and possibly expensive troubleshooting process, I would first run the current gas out of it, refill with fresh brand-name fuel (preferably non-ethanol, if you can get it locally), add a bottle of Chevron Techron Concentrate to the tank, then drive it long and hard--that's the fun part. See if it improves.

Do you know if the fuel accumulator has ever been replaced? How about the oxygen sensor?