If white exhaust smoke, leakdown test first ?

[84 500SL Euro]

My '82 380SL, WDB 107 045 12 01 5278, emits a small plume of white exhaust smoke if the accelerator is floored on takeoff.

What is regarded as the best practice in resolving this matter ?

In this case I fear starting with the simplest cheapest first and have basically parked the car 'til this is resolved.

Please direct me to a sequence that has the priority of doing in a sequence beginning with that which will most harm the vehicle.

By the way, I've never done a leakdown test and guidance in this cannot be too detailed

Thanks once more,

Courtney