1995 Ford Contour clattering noise

For the past week when starting the car in the morning there was a clattering noise for a second or two and then it cleared up and the engine ran normally.

this morning the engine started with the clattering noise and it isn't going away. It almost sounds like a diesel.

the car is not drivable, the engine accelerates sluggishly and continues to clatter at any rpm. The noise sounds as if it's loudest at the front right side of the engine.