solving system of nonlinear eqs



I am new to Maxima (and I am not a mathematician). I have a system of 16 nonlinear equations (16 unknowns) that I would like to be able to solve numerically - change the values of the 23 constants in the equations and be able to plot the 16 dependent variables as a function of these constants. 

I experimented with small nonlinear sets of 3 to 6 dependent variables -- when I got to 6 - Maxima produced an erroneous result.

Is this something experienced by others -- or am I perhaps not doing something I should be doing or doing something I shouldn't be doing? 

	C. Limuti