Hi Steve /Sandra,
No they do not inject on every stroke otherwise we would get severe fuel dilution and high bearing surface wear, but I know where you are coming from.
The 1KD-FTV engines are HCCI Engines which stand for Homogeneous Combustion Compression Ignition Engines what a lovely acronym Aye.
The Toyota IKD-FTV engine uses UNIBUS (Uniform bulky combustion) which comprises a combination of early and late injection timing.
The operation is up to half load and speed. The concept is described by
Toyota Engineers and many papers have been written on the subject.
The early injected fuel undergoes a low temperature
reaction while the late injection serves as an ignition trigger and sets off
the high temperature reaction. The first injection or pilot injection quantity is small.
Hope this helps a little