An owner selling his 84 300SD described the car as running well when warm, but it is sluggish for “a few blocks” and then it runs more strongly.

If this were a gas car, I would immediately go towards the fuel mix being off when cold, but this being a diesel - ???.

Is it possible that this is an effect of the engine compression being low due to piston/ring wear, and once the heat has expanded the pistons it then has more compression, therefore running well “after a few blocks”? Or, is there a turbo related issue, such as the wastegate blowing off manifold pressure when the engine is cold?

I know, I know, a compression test is in order – but I’m trying to boil down the selection of cars to choose from rather than compression check half a dozen cars.

THANKS AGAIN EVERYONE!