The generator matrix

 1  1  1  1  1  1  1  1  2  2  2  0  0  0  2  1  1  1
 0  2  0  2  0  0  2  2  0  2  2  2  2  0  0  0  0  2
 0  0  2  2  0  2  2  0  2  2  0  0  2  2  0  0  2  2

generates a code of length 18 over Z4 who´s minimum homogenous weight is 18.

Homogenous weight enumerator: w(x)=1x^0+3x^18+8x^19+3x^20+1x^22

The gray image is a code over GF(2) with n=36, k=4 and d=18.
This code was found by Heurico 1.16 in 0.000694 seconds.