[ngoma]

Did the onset of the excess smoke coincide with the ticking noise?

Oftentimes a mechanics stethoscope can help pinpoint noise sources. Held on each injector. Also on each cylinder's exhaust manifold outlet, also intake manifold connections. One may sound louder, or sharper, or otherwise different than the others. If no stethoscope, a length of tubing, or long handle screwdriver pressed to ear (careful!).

Maybe unrelated but when I hear ticking I say don't overlook the vacuum pump.