The generator matrix

 1  0  1  1  1  1  1  1  6  1  1 2X  1  1  1  1  1  1
 0  1  1  8  6  5 X+6 2X+1  1 X+8 2X+7  1  X X+6 2X+2 2X  3  8
 0  0 2X  3 X+3 X+6 2X+6 X+3 X+3  X  3 2X X+6  0 2X+6  6  X 2X

generates a code of length 18 over Z9[X]/(X^2+6,3X) who´s minimum homogenous weight is 31.

Homogenous weight enumerator: w(x)=1x^0+78x^31+246x^32+328x^33+852x^34+822x^35+1390x^36+1542x^37+858x^38+276x^39+96x^40+18x^41+26x^42+24x^43+4x^45

The gray image is a code over GF(3) with n=162, k=8 and d=93.
This code was found by Heurico 1.16 in 0.0282 seconds.