So...taking my long stored W124 for its maiden voyage. Taking it slow and things seems to be going well. I go to accelerate and the engine bogs down and dies. It restarts fine and I go a little further and dies again. Get to a gas station and check things out. I got a little whif of transmission burning up smell, so I check trans fluid and its a little low. I add some trans fluid and decide to head back. Dies about every quarter mile or if I get above about 25 mph. It seems to be getting at least into 2nd gear, but not much more without dying. On one occasion, it started to die then began bucking, like it wanted to go. After a few violent chugs, it surged then died.

I've replaced plugs, wires, and distributor, both fuel pumps and filter, and drained tank to get rid of old gas. It idles smoothly and does not stall or dies when throttled up in park or neutral. This only occurs in gear. The burning smell has not returned.

Any thoughts before I throw in towel and take it to a shop?

Thanks
Dan