  The samples of (Mn$_{1-x}$Co$_x$)Si with $x=0.15$ and $x=0.17$ were grown and
their physical properties: magnetization and magnetic susceptibility,
resistivity and heat capacity were studied. The data analysis included also the
previous results at $x=0.057, 0.063, 0.09$. The indicated doping MnSi with Co
completely destroys the helical phase transition whereas basically saves the
helical fluctuation area normally situated slightly above the phase transition
temperature. This area spreading from $\sim$5 to 0 K is not changed much with
doping and forms some sort of helical fluctuation cloud revealing the quantum
critical properties: $C_p/T\rightarrow\infty$ at $T\rightarrow0$.
